Kazuo

((While Kazuo Matsuzaki's design and name are straight out of canon, there is nothing else in his source material about him, and so this article is purely WTTPYLS canon.))
Kazuo Matsuzaki is the alter personality of Leon Kuwata, created as a defense mechanism against the treatment he received from his family.
Originally residing in Leon's body, he now has a body of his own and uses it to its full potential by drinking, smoking, doing hard drugs and having a lot of sex with strange men for money. Kazuichi Souda, however, is trying to help him and it's definitely working; Kazuo is nowhere near the instinctual beast he used to be and is learning more about being human and what it means to care about people.
He is thin and very frail from illness, his body doesn't absorb nutrients the way it should. If not for the fact that he eats Big Macs like they're going out of style, he'd probably be dead.
He is extremely angry and violent, and tends to just go do whatever he wants. He's very big on having personal freedom, having been restricted to someone else's body for so long, and telling him what to do generally ends in disaster. He hates being tied down to anything or anyone, and Ishida in particular gets upset about this. 
He has a thick Brooklyn accent.
==History==
im workin on it chill out wikipedia dont tell me what to do dont put all this pressure on me
==Relationships==
Leon Kuwata - If there was ever a gauge on how much hate could be harbored towards one person, Leon and Kazuo's relationship would be the maximum. Kazuo LOATHES him and everything he stands for. He hates how controlling he can be towards Souda, he hates him for being the reason he doesn't know about the world, and he hates him because he just fucking hates him. They're constantly at each other's throats and their arguments and fights cause Souda a lot of distress. 
Kazuichi Souda - Kazuo wants to bang him, that's pretty obvious. But he is not in love with him. No chance. No way. He won't say it. (He is.) When it became obvious that Kazuo didn't know anything about being a real person, Souda promised to help him become a decent human being. Aside from Ishida, this is the only positive treatment or kindness Kazuo has ever received. Kazuo will defend Souda to the bitter end, and he's risked his own life and safety for him on many occasions.
Ishida - Ishida is Kazuo's hate-boyfriend or, as the homestucks would call it, his kismesis. Being in similar but as far as not knowing how being a person works due to being stuck in another body and unable to emerge whenever they want, they seem to have stuck together and bonded. Ishida calls him (aside from 'Wannabe') his boyfriend, though Kazuo sees them more as just fuckbuddies which causes a LOT of arguments and grief and violence on Ishida's part, especially when Kazuo does his actual paying job of having sex with strangers. They hate each other and beat on each other and scream and pull hair and bite and have a lot of sex with each other, and they wouldn't have it any other way. (Well... Ishida might. That's another story.)  It's just how they are and it works just fine for them.