175 cm (5'9")
60 kg (132 lbs)
Karma is fairly tall for a middle schooler with mid-long red hair and light-coloured eyes. It is shown that he has exceptionally sharp canine teeth. He is slender and has a rather innocent face which hides his fighting strength and violent personality. He ordinarily wears the pants and dress-shirt of the school uniform, but also wears his own plain black jacket over it.
Karma is well-known throughout the school for his violent behavior and troublesome attitude. Due to his original homeroom teacher 'betraying' him, he began to hate all people who called themselves 'teachers' and as a result has almost zero respect for any adults. He is shown to be be tricky and manipulative, and takes great pleasure in harming others. He excels at using weaponry and foul play and is the only student thus far to have successfully injured Korosensei.
Karma has been described by Karasuma as "at first glance, he comes across as being a lazy sort, but... there's a strong sense of mischief in his eyes." Karma's personality is quite relaxed most of the time and he occasionally skips out on things he finds boring, such as the school assembly which required Class E to go down to the main school building. When fighting, he becomes brutal and has no qualms of hurting people who threatens him or any of his friends from Class E. It is also shown that he is one of the most intelligent people in the entire school, shown to be ranked 4th out of all 186 students in Kunigigaoka. He does not, however, want to return to the main building, stating that he finds assassination much more interesting. He has mentioned that he has a slight interest in Okuda Manami because he thinks she will be able to whip up shady medicines and chloroform that he could use for his pranks. Regardless of his lazy personality, Itona has stated that Karma was probably the strongest within the class despite him not excelling in any particular subject (shooting, knifework, etc). Most likely this means that Karma prefers to stick to tricks and pranks for assassinations rather than going into full-out combat. It has been mentioned by Karasuma that Karma likes to humiliate his opponent.
Despite all this, Karma is actually a very decent person. The reason he was placed in Class E was because he had rescued a senior from Class E being bullied by students from the main building. He was, unlike his classmates, unprejudiced against them and still considered the senior a 'senpai'. He and Nagisa were in the same class during their 1st and 2nd years, then continued to be classmates after being dropped to Class E. Perhaps, because of this, he seems to be closer to Nagisa than the others in the class.
Karma had for a long time been a rebellious student with a problematic attitude. However, due to his good grades, his homeroom teacher (from Class D) had supported him and proclaimed that "as long as you are in the right, sensei will be on your side!". One day he had found a senior from Class E being bullied and had jumped to his rescue, severely injuring his classmates in the process. Convinced that he was still in the 'right', he was shocked when his homeroom teacher told him that he was in the wrong. The teacher then further elaborated that he had no right to protect a worthless piece of trash from Class E and instead injured a fellow student with a bright future. The teacher then told him that starting his 3rd year he would be dropped to Class E. This caused the teacher's worth to 'die' in Karma's eyes, also causing Karma to stop caring about teachers in general and instead focused on doing what he wanted.
Nagisa seems to be the only one that Karma is willing to listen to, as well as Karma's closest friend in school. The two of them had been classmates for all three years in Kunigigaoka, and as a result know each other well. The two often hang out together and seem to enjoy the same things like movies. Nagisa has once stated that he envies Karma's easy-going, brilliant personality. Karma is sometimes seen asking for Nagisa's advice or intel.
During the school trip, Karma was asked by his fellow male students of which female classmate he liked. Karma replied that he liked Manami Okuda. However, upon further questioning, Karma added that it was because she could whip up a bunch of shady chemicals for him to play around with. Maehara's reaction upon this confession was: "I really don't wanna let the two of you hook up..."
- (To Korosensei, Chapter 14) "Even if the questions change, it makes no difference to me."
- His first name only appears in kanji (業) during his formal introduction. The other students, and eventually also Korosensei, refer to him with the katakana version of his name.