Can Unity make H-game?
No.
Unity can't produce a high enough temperature to ignite fusion of hydrogen atoms. Hence H-gaming cannot be achieved on Unity.
You could however request this as a new feature here
If you're referring to hentai games...
I don't get why you couldn't make such a game with Unity. A game is a game, Unity is capable of creating just about any sort of game. How you'd go about though, that's up to you. I certainly have no experience with H-games.