Kazuichi is a highly emotional character, though he tries to play it smooth and acts carefree at first. He is a very jumpy person, easily scared and often screaming in fear. People tend to note his scary appearance does not match his compulsive and cowardly personality. Naturally, he has a great fear of dying on the island, which causes a lot of stress and panic for him.

Kazuichi also has a tendency to neglect his need for a verbal filter, and blurts things out without thinking. He also seems to be a very bad liar, leading him to be contradictory at times. While he is a genius with machinery, he appears to be a bit slow-witted otherwise. Like Mikan Tsumiki, he is commonly Monokuma and Hiyoko Saionji's target and often ends up being the butt of their jokes.

Being the Ultimate Mechanic, Kazuichi is normally trying to repair any broken items on the island with his ability and familiarity with mechanisms. He tends to carry around a spanner/wrench and he turns anxious if he cannot tinker with something. He has great love for machinery, especially fast ones like rockets and bikes, which is ironic because he suffers from a bad motion sickness. At times, his love for machinery seems to reach even abnormal levels. In Island Mode, he appears to question his sexuality around Hajime Hinata (for example, he has excited and then confused reaction about taking clothes off with him and he's afraid he'll dream about a date with Hajime after he jokingly suggested a one), only to comically confess to him that he is attracted to tanks. In Chapter 3, it's also revealed that he apparently likes the idea of undressing a girl and checking out her bone structure, since he thinks it's similar to dismantling machines. He seems to think it's normal, though Hajime is weirded out by this and calls it a fetish.

Kazuichi also likes girls a lot, though in a rather perverted and shallow way. He has taken a strong liking to Sonia Nevermind, to an extent of being a pervert, somewhat stalker-like and in constant jealousy of Gundham Tanaka. He claims that he's dreamed of a beautiful blond girlfriend since he was a kid and his affection towards Sonia seems rather shallow, as he actually seems to dislike some of her actual personality traits, like her love for occult. Sonia dislikes this behavior and calls him a stalker. According to Kazuichi, after he changed his appearance in the past, some girls took interest in him and he was actually a bit frightened by this.