On the official World Trigger Twitter, Ashihara answers questions from fanmail. After a while they are gathered into the manga volumes:

Volume 5 - Question Corner 1Edit

Q: Do Border personnel get paid?
A: I might show it one day, but yes, agents do get paid. B-Rank agents get a fee per Trion soldier they defeat. A-Rank agents have a salary + fee per Trion soldier. C-Rank trainees do not get paid.

Q: Are there any requirements, like fitness tests, for applying to Border?
A: There are basic fitness tests, nasic achievements tests and an interview. Other than having low Trion levels or a criminal record, you won't get rejected (Osamu was nearly rejected).

Q: Can the Trion gland be strengthened with training?
Q: Does Trion get replenished with time or sleep?
A: Just like lung capacity and muscle strength, it can be improved somewhat, and does recover with nutrition and rest.

Q: Why are all Border agents young?
A: The biggest reason is that the younger you are, the more your Trion gland can grow. Agents over age 20 whose growth has stopped often go into administration (like Sawamura).

Q: Do Border high schoolers go to the same school?
A: For better coordination of agent schedules, they often go to the same school, but they don't have to.

Q: Do Trion bodies feel pain from Trigger attacks?
A: There is a pain sensation that tells you what part of your body got damaged. This can be turned completely off.

Q: Can you use Trion to heal damage?
A: It is impossible to repair a Trion body. The combat body is basically disposable. Once destroyed, you need to create another one, which takes time and more Trion.

Volume 5 - Question Corner 2Edit

Q: How do you become an operator?
A: You can be one from the very beginning or, you can change from a combatant to one.

Q: Why is Bamboo Shoot faction's Narasaka pretending to be a Mushroom?
A: To avoid unneccesary bloodshed.

Q: Are all operators female?
A: Nearly all, because it is said that women have higher parallel-processing capabilities. Men can become operators, though. However, on the flip side, almost all engineers are men. The men are seeking comfort.

Q: Is Raijinmaru male or female?
A: By looking at its face, it appears to be female. However, I believe everyone in Tamakoma thinks it's male.

Q: Is there a limit for number of people per team?
A: The limit is 4 combatants and one operator, so 5 people is the maximum. The reason is that any more than that would surpass the operator's parallel-processing capability.

Q: In Chapter 2, did Yūma eat Osamu's lunch?
A: It was his own lunch.

Q: Why are only Osamu and Chika's clothes different? Can you change it?
A: Chika's clothes are a female C-Class sniper's standard uniform (until junior high). As for Osamu's, Jin arranged for it. That's why it has the Tamakoma emblem.

Q: What is Osamu's eyesight?
A: Both eyes are 0.2.

Q: Does Osamu take off his glasses when he bathes?
A: Probably not. I doubt he takes them off even when he sleeps. Always glasses.

Volume 6 - Question Corner 3Edit

Q: Does Arashiyama not have parents?
A: He does. His father is a company employee, and his mother has a part-time job and is a housewife. His grandmother, younger siblings, and dog also lives with him.

Q: What part-time jobs does Torimaru have?
A: Various jobs like newspaper delivery, supermarket cashier, waiter at a restaurant, etc. It's rumored that during Torimaru's shifts, the amount of female customers doubles.

Q: What does Ashihara-sensei think of Osamu’s tendency to break out into sweat?
A: Osamu's relationship with cold sweat is similar to the relationship between omurice and ketchup (the glasses are the egg).

Q: Is there an age-limit for enlistment?
A: If your Trion is particularly high, then there is no age limit, but young Trion organs have greater growth potential so they are more likely to be hired. Youth certainly has its advantages.

Q: Can Teleport be used continously?
A: Distance moved = Trion consumed, so there has to be an interval. A long-distance teleport (30m or more) will require a few seconds, but a short-distance teleport (2-3 m) will take about 0.5 seconds.

Q: Which is the abbreviation for World Trigger, "WāTori" or "Trigger"?
A: The editor uses "Trigger", but the manager uses "WāTori". The assistants and I simply say "World Trigger".

Q: How far can Jin see into the future?
A: I believe that he can see established futures (futures where potential of realization is rather high) pretty far counting by years. On the contrary, futures where he can intervene (uncertain futures), he can only see comparatively recently.

Q: Who has the greater Trion ability, Chika or Izumi?
A: Chika. Izumi is a genius, but Chika is a monster.

Q: Was Raijinmaru bought from a pet shop?
A: Branch chief Rindō brought it from out of nowhere. It's a mystery.

Q: Why is Kazama-san so short?
A: Small and efficient. That is Kazama-san.

Volume 7 - Question Corner 4Edit

Q: How are Trion suits made and decided?
A: There are different basic designs, and it is arranged for each team. A common design is a tracksuit style that doesn't intimidate civilians. There are also suits with original modifications that include special functions like Kazama Unit's.

Q: Is Trion amount hereditary?
A: There is some probability that Trion is hereditary, but parents' Trion ability is not necessarily passed down. For example, Chika's parents' Trion is not particularly high.

Q: Do Operators participate in expeditions?
A: Like Usami said in volume 3, operators seem to accompany their teams during an expedition. Border have mobile computers which run on Trion, so they can support units even on expeditions when there's no power.

Q: Please tell us how many ranks both A-Class and B-class teams can go down to.
A: Currently, A-Class has 8 teams and B-Class has 20 teams but they move up and down during Rank Wars so their ranking can change at any time.

Q: What is Reiji's best dish?
A: ‘Meat meat meat veggie stirfry’ (a meat and vegetable stirfry with three times the normal amount of meat). One of the standard dishes at Tamakoma.

Q: How do newly-enlisted personnel find themselves a mentor?
A: The first step is to find videos and matches of a capable person. When things have started to form to some extent, they can directly ask them, or have someone intermediate to become their student. They can also just keep fighting in individual rank battles.

Q: Is there anyone who has risen to A-Class without a mentor (original members excluded)?
A: Yes. Izumi, Kikuchihara, Yoneya, etc. You can become strong even without a mentor if you have a rival.

Q: When Tachikawa cut up the Ilgar, did he use Teleport, or did he jump from the roof?
A: I think he used Grasshopper, which is a Trigger for maneuvering in battle, to jump through the air. Midorikawa has used this Trigger as well.

Q: Do all the A-Class high schoolers go to the same school?
A: There are 2 schools (regular and university-preparation) that are affiliated with Border. Kodera, Narasaka, Usami, Utagawa, Kikuchihara, etc., go to the preparatory school. Pretty much everyone else goes to the regular school. There are also people like Konami (and Kitora) who go to posh girls’ schools that aren’t affiliated with Border.

Q: When one uses their Trion body, where does their original body go?
A: It is swapped in the Trigger Holder space, where the Trion body usually is.

Volume 7 - Question Corner 5Edit

Q: Please tell me about the gun Trigger (Shotgun) Suwa was using in chapter 45.
A: It is a shotgun trigger that fires large normal bullets in consolidation. You can adjust the angle of the bullets’ dispersal to a certain point. Its advantage is its high instantaneous firepower, its disadvantage is that there is a pause between shots which can create an opening.

Q: How far can you change the shape of a Scorpion? Can you wear it around your whole body?
A: You can change its shape quite a lot. How far you can extend it depends on the trion ability of the user, but the more you extend the more its strength drops, so if you wear it around your whole body it will be as fragile as glass. If it’s Chika she might be able to fight with it around her whole body.

Q: If Tachikawa-san, who seems to be quite a disappointment outside of battle, has any fail episodes, please tell us.
A: He read ‘DANGER’ as dan-gah, he made a fuss about a computer being broken when it was just not plugged in, he only ate the dried fruits in a fruit granola bar, and so on.

Q: Why are Osamu’s glasses an under rim style?
A: He received his father’s frames. (His father is still alive)

Q: Is there a meaning in the distinction between using either ‘sempai’ or ‘san’?
A: It seems that generally the middle and high schoolers get ‘sempai’ and anyone older than that is called ‘san’. In other words, Osamu calling Kazama-san ‘Kazama-sempai’ means…
(trans: Ashihara is probably trying to say that Osamu thought Kazama was a high schooler from his height, hence why he called Kazama ‘sempai’ when Kazama’s age should merit him ‘san’.)

Q: The dots on Kazama Unit’s uniform reacted when they activated Charmeleon. What was that about?
A: A mechanism that decreases the amount of trion used in Charmeleon was included in their uniform. The cost for the combat body itself becomes higher because of that.

Q: Is Utagawa-kun an Attacker or All-Rounder?
A: The comics are wrong here and there; he is an All-Rounder.

Q: Kogetsu ‘cannot be freely extracted or withdrawn’, is that only while Kogetsu is in use? Or does this apply for the entire time the trigger is activated?
A: It applies for the entire time after you’ve chosen the Kogetsu. Sometimes it looks like the Kogetsu had disappeared, that’s just the author forgetting to draw it. The author frequently forgets to draw things.

Volume 8 - Question Corner 6Edit

Q: How heavy is one shot from Miwa's Lead Bullet?
A: I think it's about 100 kg. Yūma's Anchor is about twice as heavy, though.

Q: Please explain the relationship between Tsukimi-san and Tachikawa-san. (From their birthdays Tachikawa-san seems to be older, but she called him ‘Tachikawa-kun’)
A: They are childhood friends, she was his teacher in tactics. The line is, Azuma-san ⇒ Tsukimi (and a whole lot of other disciples) ⇒ Tachikawa.

Q: When you use Trigger On, your Trion body has a Border uniform, but does the Trion body come with the uniform?
A: When you activate your trigger, you can choose between ‘changing into a combat body with designated attire’ or ‘changing into a combat body with the clothes you’re wearing’. You can register several outfits and freely choose between them.

Q: Is Yūma’s wounds healing after he got hit by the car due to his trion body restoring itself?
A: That's right. Yūma's usual trion body has less durability than his combat body, but in return his usual body can heal itself. I believe that a regular combat body will not be damaged when hit by a car.

Q: Do Sniper rifles always have the same form? Can they pull it in or out freely, or can they shrink it?
A: When you take it out, then it will stay in that form. When you deactivate it, the next time you take it out you will need to use up a gun’s worth of trion again.

Q: Can All-Rounders snipe?
A: Fundamentally, no. All-Rounders generally fight in melee to mid-range. Only Reiji-san is a perfect All-Rounder who can also snipe.

Q: Does having good eyesight matter for snipers?
A: Your eyesight in a combat body is restored, so flesh and blood eyes do not matter. However, characters with glasses retain them to keep their identity.

Q: Is Satori's Twin Snipe a super-skill, or is it a result from daily practice, and he just has a knack for it?
A: It's the result of daily practice. Seeking both firepower and coolness, this was one such completed version he came up with. However, no one else mimics it.

Volume 8 - Question Corner 7Edit

Q: Is Konami-sempai’s short hair in her combat body to save trion?
A: It seems she did it so it won’t get in the way while fighting. It looks like she set it to her old hairstyle.

Q: If Tokieda likes cats, does he have any at home?
A: He keeps 2. A black-ish tabby cat named Arthur, and a white cat with black spots named Tomio.

Q: Why does Yōtarō wear a helmet?
A: Because he always gets himself into a fight. The helmet was made by Reiji.

Q: Which is the protagonist of the series, Yūma or Osamu?
A: Either one is OK. For me, all four of the characters drawn on chapter 1's title page are the protagonists.

Q: If you munch on Bonchiage from Jin's room without permission, will you get yelled at?
A: Bonchiage will be delivered to your room without permission in return. In boxes.

Q: Do gates only open within Mikado City? Have any opened outside of Mikado City?
A: They open secretly all over the world and steal people away without anyone the wiser. Because gigantic ones opened up with a bang within Mikado City, the world believes it only happens to Mikado City.

Q: If Tachikawa-san was trained to sword fight in Shinoda Faction, why is he in Kido Faction?
A: Kido Faction places an importance on expeditions, Shinoda Faction on defense. Tachikawa is interested in expeditions into the Neighbourhood. He's not at odds with Shinoda-san or anything.

Q: Do expeditions try not get noticed by that nation?
A: Basically they sneak in then get their hands on trigger technology through negotiations or bartering. It seems they also take triggers when they fight back against people who attack them in nations that are at war.

Q: Since Arashiyama and Konami-chan are cousins, did they enter Border at the same time?
A: Konami was just really early when she entered Border. While Konami is a senior in Border from the early days, Arashiyama enlisted when the current HQ base was created.

Q: Does Kikuchihara like anything?
A: Buddies and friends.

Volume 9 - Question Corner 8Edit

Q: Rinji-san is Osamu’s sempai, but how can Osamu call his sempai’s sister (Chika-chan) without any honorifics?
A: Because he has no shame, not. It’s because Rinji-san and Chika told him ‘no honorifics is fine’.

Q: Does the New 3 Idiots team have a formation other than the Rooster Battle Formation?
A: There's the Dragon, Snake, Horse, and others to make a total of ten. 9 of them are unison attacks, but 1 of them is a full-throttle getaway.

Q: If you cancel the transformation yourself, do you still need to remake a trion body like when you bailout?
A: When you cancel the transformation yourself, the situation is treated like you have ‘shut away' your trion body. The next time you transform, you can still use that same trion body, but the damage isn’t fixed.

Q: Is the trap wire that Reiji-san used the same as Kitora's? Also, is the box used in the attack Meteora?
A: It is the same as Kitora's, and called Spider. Various other Triggers can be used in conjunction. The box in the trap seems like Meteora (27 divisions).

Q: Izumi combined Viper + Meteora to make Tomahawk, but was it his genius that allowed him to do it? If Osamu knows how and trains, can he do it too?
A: He can, but it will take him time to combine them. If Osamu tries to shoot a Tomahawk right now, it will take him about a minute’s time to combine them. It takes Izumi about 2 seconds.

Q: During the fight against Lamvanein, shields were set up remotely, but how far a distance can you cover?
A: It changes a bit depending on individual ability, but the distance is about 25m. This remote shielding is one of the areas where Shield surpasses Raygust('s shield mode).

Q: Does B-rank units have no emblems? Can only A-rank units have emblems?
A: As long as you were A-rank even once, your unit has their own emblem. Even if you are demoted to B-rank you can keep using it. If the unit breaks up then the emblem is gone too.

Q: If one didn't say "Trigger On", would they still be able to transform?
A: As long as you are touching the trigger holder, and make your activation intent clear, you can say nothing or say something else. You can swap bodies even if you use an original transformation call.

Volume 10 - Question Corner 9Edit

Q: Please tell us if there are any characters who are living in Tamakoma branch.
A: Branch Manager Rindō, Yōtarō, Jin, and Reiji-san live there, but rooms are provided for everyone and people like Konami or Usami frequently stay over. There are plans to provide rooms for Osamu, Yuuma, and Chika too.

Q: During the battle versus Lamvanein, Okudera-kun used Fullguard; does that mean you can use other triggers if you just put the Kogetsu in a sheath without deactivating it?
A: Even without putting it in a sheath you can turn the Kogetsu OFF, but the sharpness will become zero. You won’t be able to use it and you can’t deactivate it either so it’s a big hindrance. Deactivating the Kogetsu and then remaking one later when you need it again will mean it’s not a hindrance, but it will use up trion. It is the same as gun type triggers.

Q: Do trion organs decay with age?
A: It seems it slowly decays if it is not used. Using it maintains it to a certain extent.

Q: What is Osamu’s favourite out of his mother’s home-made dishes?
A: Cream croquettes. Even the white sauce is hand-made.

Q: Are all the agents from Mikado City?
A: Generally they are, but scouting occurs in other prefectures too so there are a small number from other regions.

Q: What is it called when shooters produce trion in cube form?
A: Trion cube, nata de coco (fermented coconut cubes), sugar cube, Suwa, tofu, etc. Everyone calls it whatever they want.

Q: While Chameleon is in use, can Hound bullets track you? And do you show up on Radar?
A: Hound bullets that use ‘Sensor Guidance’ can, but usually they are intercepted by walls and so on. Even during Stealth Mode, you still show up on Radar, so it’s possible to use that to make a rough counter-attack.

Q: Yūma’s C-rank uniform is black; was this also specially arranged by Jin-san?
A: It seems to be something that Yūma’s father, Yūgo, had configured a long time ago. It is a remnant from the times of Old Border.

Q: Why is Suwa-san smoking even though he’s in a trion body?
A: It’s to show off. Since there have been no depictions of ashtrays, there is also the possibility that it might not actually be a cigarette.

Volume 10 - Q&A from Jump Festa 2015Edit

Q: Can Replica eat food??
A: He cannot gain nutrition from food, but as a poison taster he can eat it. Good for survival.

Q: What’s the reason behind Jin-san’s sunglasses not slipping?
A: It’s connected at the back.

Q: Can Replica sleep?
A: He doesn’t need to sleep to recharge, but he does have a ‘sleep mode’-like feature. To stay out of the way when he isn’t needed, he is on standby (sleep mode) in the ring.

Q: Out of the current characters, who is about as strong as Yūgo?
A: Yūgo was as strong as the current Shinoda-san. Four years ago, Yūgo would have been stronger, but Shinoda-san trained every day and caught up.

Volume 13 - Question Corner 10 Edit

Q: In the end, did Satori have to face any penalties after Chika blew a hole in the wall of HQ with that Ibis?
A: It seems that, due to Azuma-san and Arashiyama covering for him, he got away with just a chop from Kinuta-san.

Q: What is the difference between ‘turning off Kogetsu and then recreating it’ and ‘putting away Scorpion and taking it out again’?
A: ‘Putting away Scorpion’ is similar to ‘putting Kogetsu back in its scabbard’. They’re both out of the way, but Scorpion is less of a burden. ‘Turning off Kogetsu’ means to destroy both the scabbard with the blade.

Q: What distance is the limit for a sniper trigger to hit its mark?
A: If it’s an unmoving target, someone who is good at premise sniping like Narasaka or Hanzaki can hit the mark from 1km away with an Egret. An Ibis or Lightning’s range will be shorter.

Q: Even though Yūma doesn't need to sleep since gaining a Trion body (chapter 94), does he get hungry?
A: I believe that Yūma needs to eat food to send nutrients to his near-death body, so he eats more than others.

Q: Does normal trion body users also not need to sleep but need to eat?
A: Trion body users need rest just like usual. This is because the brain and nerves get fatigued, and because the trion organ does not recuperate while using a trion body.

Q: Does Raygust’s shield mode fit in one trigger?
A: Shield mode is not an option but one of Raygust’s standard functions. As such it does not use a trigger slot.   

Q: Are there any differences in the amount of time it takes a person to recreate a trion body?
A: The more trion a person has (= the more trion that gets used in battle) the bigger the cost of constructing a combat body, so recreating it will take more time. Chika takes a lot of time but Osamu can return to battle fairly quickly (in about 1~2 hours time).

Q: What do Border Agents do on their days off when they’re not on duty and there’s no school?
A: Polishing their skills in solo rank battles, studying the recordings, immersing in hobbies, feeling sad, falling asleep, thinking about what to buy with their wages, being swamped with homework, playing around, dancing with joy, visiting grave sites, or thinking about the person they like.

Volume 18 - Question Corner 11 Edit

Q: C-rank members are only supposed to have one weapon trigger, but why did Chika train with a bagworm on at Tamakoma?
A:That was a Tamakoma trigger that Reiji-san provided to drive the foundations of sniping into her. It is set with the three types of sniper rifles and bagworm.

Q: Are there any branches besides Tamakoma and Suzunari?
A: Border has 6 branches: Tamakoma, Suzunari, Wataayu, Yumite District, Hayanuma, and Kuma. Its personnel are mostly those who prioritise work or school and don’t aim for A-class (they do not participate in the twice a week Rank Battles). The branches are placed on the outer edge of the Danger Zone. Other than Tamakoma, the branches function as a point of contact for local residents.

Q: How is an all-rounder defined?
A: An all-rounder is ‘an agent who has earned more than 6000 solo points in both Attacker and Gunner triggers respectively’. Right now Border’s overall level is on the rise and there are those who say it should be raised to above 8000.

Q: How do you think of names for the characters?
A: Surnames are just ones that fit, roll off the tongue easily, and isn’t too unique. First names are chosen by thinking about the parents that would be picking the names for these people.

Q: Can’t you train your trion organ in Virtual Combat Mode?
A: You can’t. You can only train your reflexes and increase combat experience in virtual mode. Trion organs can only be trained through using trion.

Q: What is the difference between Shield, Raygust (shield version), and Escudo?
A: Shield: Can change shape. Durability changes according to the size of the surface area. Moving it lowers the durability.
Raygust: Can change shape. Durability changes a little according to the size of the surface area. Even if you wave it around in your hand the durability will not change.
Escudo: Cannot change shape. Cannot be moved. High durability. Needs a place (such as a wall or floor) to grow out of.

Q: Can Escudo defend from Lead Bullets?
A: Escudo converts trion into a material form, so it can. It is treated the same as blocking Lead Bullets with walls or buildings.

From Twitter - April 2014Edit

Q: If you become B-rank or A-rank do you have to join units? (I want to read about the stories behind all the units’ formations)
A: To participate in rank battles, at the very least you need one combatant and one operator. Naturally, it’s more advantageous to have more members, so a unit with few members is quite a thorny path in comparison.

From Twitter - January 2015Edit

Q: When enemies show up on radar, is it possible to use that to snipe?
A: Compass points are displayed on radar, but not elevation, so it seems impossible. Combined with the topography data that operators have, it is possible to grasp the approximate location of the mark, but it would be hard to pinpoint a human-sized opponent this way.

From Twitter - February 2015Edit

Q: Are radars and wires option triggers?
A: ‘Radar’ is a standard equipment trigger like trion bodies or the bailout function. ‘Spider’, a trigger that uses wires, is an option trigger.

Q: Is Kunichika from Hokkaido? (trans: a reference to the fact that her favourite food is ishigari nabe/salmon hotpot, a traditional Hokkaido dish)
A: Her mother is. Her parents would send salmon hotpot sets, sea urchins, crabs, salmon roe and so on to them. Everyone eats them together.

From Twitter - August 2015Edit

Q: Why does Arashiyama and his siblings have ‘second position’ type names?
A: The person who named them, Arashiyama’s grandfather, apparently had something in mind when he chose them, but since he has passed away nobody knows for sure. The three of them seem pretty happy with it.   

Q: How many Mini-Replicas can be released at a time?
A: If the functions are limited to conversation and transmitting over the comms he can probably release about 200 of them

From Twitter - September 2015 Edit

Q: While you are in your trion body, where is the trigger holder that houses your flesh body?
A: In another dimension (a dimension on the Neighbourhood side) an independent space has been set aside for the trigger holder to be stored.