Yuuma Kuga

Yuuma Kuga is one of the main characters from the World Trigger anime and manga.

Yuuma is a humanoid neighbor from an unknown world who illegally came to Earth and joined the same class as Osamu.

In the AWA fics, Yuuma is a student at the AWA Academy and is part of Class 6.

Appearance
Yūma is shorter than the average for his age range. He has white hair and red eyes. It is later revealed that his hair was originally black and his body had stopped growing since he was 11 years old because it was made out of trion, thus explained his short stature.

He wears a blue suit top and gray bottoms traditional of Japanese high school students. When not in Trigger mode or school uniform, he usually wears a purple hoodie with a paw symbol and the text "UMA" (which stands for "Unidentified Mysterious Animal"), and beige baggy jeans pants.

In Black Trigger mode, Yūma gains a black jumpsuit which Replica fuses itself with. In C-rank trigger mode, unlike most other trainees, he gains an all-black uniform, instead of the classical all-white one; it has a black jacket with thick white stripes running down from the sides of his collar to the sides of his sleeves and also around his collar and thin gray stripes in the borders of the zip fastener and collar.

In B-rank trigger mode, he has a uniform similar to Osamu's, except his jacket's left sleeve doesn't have a shoulder guard. His right arm also has the same design as his left, unlike Osamu's, making his jacket more symmetrical. Also, the black stripes on his jacket's sleeves are thinner and, unlike Osamu's, don't have white stripes in the middle, and the black stripes go over his shoulders and collar. On the sides of his shoulders, he has Tamakoma Branch emblem, surrounded by the stripes. In addition, the sleeves of his jacket somewhat merge with his gloves, and he tucks his pants inside his boots, like when he was a C-rank agent. His Unit's emblem is located on his left chest.

Personality
Yūma has a laid back personality and is not very knowledgeable about Japanese customs, being from another world (despite having a Japanese father), leading to some run-ins with rough people. He is logical, advising Mikumo to stay away from the trion Battle Soldier rather than save the students as Mikumo could die. He seems to be aligned with Border's cause, fighting against Neighbor forces. Despite his happy exterior, he is actually deeply depressed due to his father's sacrifice to revive him.

Initially, his only sense of purpose was to revive his father, as he felt tremendous responsibility for his death. However, after meeting Osamu, Yūma decides that his purpose is to support Osamu in his goal.

Abilities
Despite his young age and even younger appearance, Yūma is an experienced warrior of rare skill. His father trained him for six years and, after his demise, Yūma continued fighting alongside Calvaria for three more years. Having received a Black Trigger from Yūgo, his combat prowess increased exponentially, which eventually led to Spinthir withdrawing its forces. Yūma's Black Trigger is even more effective in battle when Replica assists him in the overlapping and combination of seals and the creation of new ones, making both processes instantaneous. The Trion Warrior also helped Yūma continue his training in strategy after Yūgo's passing, and the loss of the need and ability to sleep gave Yūma even more time to spend on it.

After joining Border Yūma achieved a working command of many applications of the organization's Triggers in an extremely short amount of time and went on to hone them, eventually being praised not only for his proficiency, but also for his ability to utilize Trigger Set in completely novel and tremendously efficient ways. His fighting prowess is further augmented by the speed with which he can activate and change his Triggers, which allows him to instantly switch from attack to defense and back to offense and has prevented him from bailing out on countless occasions. Rapidly switching Triggers is also a component of his effectiveness at aerial combat, which in turn translates to Yūma possessing such high mobility that he can hold his own against whole enemy teams by quickly flitting in and out of range and turning their own teammates into obstacles for each other. Osamu’s deployment of Spider threads enhanced his effectiveness even further, making his movements even faster and harder to predict, to the point that entire units from the middle of B-rank were at a severe disadvantage when confronting him inside a wire zone. Even without them, however, Yūma was able to keep track of the movements of the members of Miwa Unit and Azuma Unit and later matched no. 6 Attacker Tatsuhito Ikoma in combat while he was assisted by Satoshi Mizukami. On those occasions he suffered notable injuries only when previously hidden Snipers attacked him, and even then he managed to mitigate the damage.

His fighting capabilities have led him to being extolled as worthy of A-rank and put him on par with some of Border's most skilled Attackers. After Tamakoma Second's second rank battle, his mentor was surprised to find out that he had been beaten by someone other than Kei Tachikawa, Sōya Kazama and herself, that person being the no. 4 Attacker Kō Murakami. Yūma currently holds a victory ratio of 38.8% against Murakami and 47.6% against Masato Kageura, even though Murakami considers himself less powerful than Kageura and has more losses than wins against him. In addition, Yūma is the only member of the trio without a Side Effect to boost his performance in battle. Yōsuke Yoneya described his movements as "quiet, matter-of-fact and deadly", adding that their sole purpose is to take out the opponent as efficiently as possible. This no-frills style reflects Yūma's single-mindedness in combat, which allows him to fight without emotion and makes him one of the only two people in Border not to trigger Kageura's Side Effect. He was also noted to excel at landing fatal blows in the middle of chaos, a skill which aids him in launching sneak attacks and at supporting his teammates in a melee.

Although swordsmanship is his specialty, Yūma has shown to be competent also at hand-to-hand combat while using his Black Trigger. He generally resorts to kicks to deal damage right after approaching an enemy and to relocate them, and to punches when he is more confident that he will be able to land a decisive blow. Additionally, he has exhibited some skill with projectiles through his Bolt seal, hitting a very distant target with Replica’s guidance.

Possibly owing to his many years on the battlefield, Yūma was able to tell that Jin was powerful at a glance, admitting that he could not determine if he would be able to defeat him even with Replica's assistance. He also assured Osamu that he would die if he fought a Mole Mod, since 20 copies of him would be needed to take one down, and only two of them would survive. His years of traveling with his father endowed him with extensive knowledge of the Neighborhood and Trion Warriors as well as of how to defeat them.

Trivia

 * "Yūma" is a combination of two words meaning "to play" and "real, genuine", together his name means "to play for real" or "playing real," which relates to his attitude as a member of Border. "Kuga" is a combination of "sky" and "leisure".
 * The creator, Daisuke Ashihara, mentioned that even without Yūma's postponed phase, he would have kept Yūma at the same height if it were not a part of the plot.
 * He also stated that he himself does not think of Yūma as small, but incorporates the concept of characters referring to him as so to show that height does not matter—also seen as how Yūma lets it slide, instead of viewing it as an asset.
 * Yūma has a habit of doing duckfaces, which have become a meme among the manga's fans.
 * Yūma tends to scare people with his eyes.
 * His "UMA" hoodie might be a reference to his name, as "UMA" and "Yūma" are homophonous in Japanese.
 * Yūma apparently dislikes being called "senpai," as he tells Midorikawa to call him just "Yūma" when the latter calls him "Yūma-senpai."
 * Ironically, he previously ordered Midorikawa to call Osamu "senpai" should he defeat him in battle.
 * He likes Japanese food.
 * He came second in the First Popularity Poll.
 * Yūma does not need to sleep, due to his natural body being made of Trion as well.
 * His nicknames in the Anime are "C-Rank White Devil" and "White Nightmare".