HELP PLEASE

I’m looking for a bl or a straight one (could also be a gl I don’t mind) where the male lead is obsessively in love with the main character to the point of being willing to kill for them. Like, he’s been in love with them for a long time, but the main character has no idea. He’s dark, maybe even evil, to everyone else but treats the main character like they’re his entire world. Meanwhile, the main character should be a sunshine-type and kind, warm, and totally oblivious to how deep the male lead’s obsession runs. Bonus points if the male lead has been secretly watching them or protecting them from the shadows for years. Any recommendations?(I don’t care about the art-style as long as the story is good and no smut isn’t a problem)