"Why do you guys hate lies so much? There's only one truth, but endless possibilities for lies, y'know? And some of them are only white lies, or lies to be kind to people... If you deny all of that *just* because it's a lie... Then that means you guys are just terrible at being lied to! Seriously, the worst!"
Appearance
Kokichi is a young man with an innocent look(innocent my ass) and a rather refined face. He has a short stature, a thin build, and very pale skin. He has purple eyes and moderately long, wavy blackish purple hair, with the tips dyed a brighter purple. In the official art book, it is stated that he does not seem to care about his hair and the hairstyle is a result of him playing with it—however, he does sometimes make use of the shadows his bangs form to make himself look evil.[5]
He wears a white suit with multiple straps wrapped around his arms, and two straps hanging loosely around his legs. Apparently, his pants are made to look like a piece of punk fashion with bondage pelts, but they are actually just fake belts sewed to thicker part of the thighs. His shirt is ripped at the hem and the collar part of it is completely gone, and big parts of the uniform are fixed with metal clips. He has multi-colored buttons running down the middle of his shirt, with a few usually hidden under his scarf, and he has military badges on his right. His scarf has black and white spaces alternating exactly like a chessboard. He also wears two-colored black and purple slip flats, and as seen in the character design gallery, he appears to wear a white belt.
In his promotional art, he is shown with a dark flowing cloak and a leather peaked hat with a gold badge on top of it, giving him a more malicious look.
In the prologue, he wears the uniform of his original high school. He has the classical tsume-eri uniform on properly. His personally customized uniform has beauty from that of a university annex high school. Like with his other attire, the bottom of his trousers are short.[6]
As a big contrast to his other clothing, Kokichi's "trendy" underwear has much brighter and vibrant colors with red and yellow stripes. Apparently, he wishes to hide his playful heart and true fashion sense in a place no one can see.[5]
In the Japanese version, Kokichi's voice is usually slightly childish fitting his appearance, but it occasionally turns much deeper and mature, usually when he is either angry, foreboding or flirty. He similarly occasionally uses deeper voice in the English version, but it's less notable as his usual voice isn't as childish as the original.
Personality
Kokichi describes himself as an evil supreme leader, and often claims that this title is the reason behind many of his questionable actions as if he is expected to fulfill his role. He is an elusive and manipulative person who unabashedly tells lies and says whatever he's thinking. He is also strangely straightforward about his supposed evil nature, openly claiming to be a leader of a large secret society, admitting to being a liar, and saying he has done nothing but bad things. Among other things, his organization supposedly has covert agents in every country, control over all the mafias in the world, torture as a form of punishment, and Kokichi's defeated opponents apparently will get sent to Siberia. However, none of his claims have been confirmed, and the other students think he's either lying or delusional.
According to Kazutaka Kodaka, Kokichi is a trickster character in the truest sense of the word.[7] He is very mischievous, and he enjoys pranks and teasing others, sometimes in quite mean-spirited ways. He appeared to have a strong need for attention, as he got irritated if people talked over him or didn't react to his antics the way he wanted them to. He also appeared quite arrogant, clearly considering himself very important part of the class trials, looking down on some of the other students, often wishing to lead the debates and once claiming that the class trials won't be good if the others won't allow him to speak. Because of his behavior, he is viewed as an antagonistic figure among the group, but this doesn't seem to stop him from being able to manipulate the class trials anyway. He is often portrayed smiling slyly and laughing mischievously, though he may look very harmless and innocent at first glance. He often behaves calmly and coolly in a way to torture the others, at times turning very ominous to the point of having very unsettling, downright demonic looking expressions. Sometimes, he can speak very sweetly, even flirty and claiming he loves the other person very much, while during other moments he can speak in a very crude and nasty manner (especially towards Miu) and use insults which vary from quite harmless to very mean-spirited. He can also try to use his looks to his advantage and sheds crocodile tears by crying loudly like a scared and threatened child, telling the others they're being really mean, but this is always overly dramatic and obviously fake. There are also moments when he appears scared, tearfully mentioning that he is afraid of the killing game and doesn't want to die, and often crying loudly soon after someone's death...but it's unclear if he is being genuine or just trying to earn sympathy with his looks. There are also moments when he suddenly falls asleep and snores comically, angering the others.