Just your average shonen series. Kyo seems to enjoy fighting, as well as fighting, and fighting. His hobbies include fighting, fighting, and fighting. In his spare time, he likes to fight.
Seriously, there are two personalities sharing one body in SDK. One is Kyoshiro Mibu, who seems to be a mostly harmless medicine salesman with a weakness for the ladies. The other personality is Demon Eyes Kyo, the legendary Killer of 1000 Men. While his main ambition is to be the strongest fighter in the world, and he isn't what you would call a nice guy, true to cliche he's not quite as bad as rumors make him out to be. Unless he doesn't like you, in which case it wouldn't be too hard to motivate him to kill you. Kyo does not like most people.