Fourthwalling: Considering Harry's nerdy knowledge base, its possible that he knows something about some canons, so its okay for some people to know about his.
Touching, hugging, flirting, kissing... : Harry, in general, is a bit awkward, being so tall and such. He might react badly, depending on the situation.
Fighting, Injury, Killing: No death or major dismemberment without a lot of discussion before hand. But otherwise, its a rule of his canon that he be punched, kicked, shot, burned, electrocuted and generally beat within an inch of his life every book.
Anything specific for this character? Harry will make anything that isn't specifically game-protected technology eventually short out and go boom.