A Happy Ending with the Paranoid Villain [Quick Transmigration]

In many stories, there is a villain who stands against the protagonist. They may be calculating, cruel, devious, or ruthless in their methods... but in the end, they all meet a bad ending. Xu Chang'an's mission is to travel through various novel worlds and set these villains straight, giving them a happy ending. When he first received his mission, Xu Chang'an thought it couldn't be easier. Until... The aloof (fake) campus heartthrob falls for him. The overbearing (scared out of his wits) CEO falls for him. The refined (degenerate) movie star falls for him. The white lotus (black to the core) disciple falls for him. The germaphobic (pervert) forensic doctor falls for him. The imperial (not really) marshal falls for him. The idiot (this one's real) zombie falls for him. The sinister (putting on an act) leader falls for him. Xu Chang'an: "Thanks, but no thanks! I'm a top, and I don't like being topped." Top: "Look at my name." Message: The land is at peace, and heroes return home.