any manga that has a really possessive "hero", like Ryoki from Hot Gimmick, he was so possessive and obsessive with the heroine....do you know of any others heroes similar to the one in Hot Gimmick- can be boy/girl, or BL/yaoi
others I can think of that have a crazy possessive hero: 100% Perfect Girl Vampire Knight Cornered Mouse Dreams of Cheese Black Bird Scarlet
Have you tried the Possessive lover tag? Maybe you have XD
Hmm maybe something like komatta.... i dont know the rest of the manga name, sorry, but it's my favorite It is shounen ai, sort of.
Edit: I checked my list, I think there's only 3 that I'm currently reading that have possessive lovers. And they're all BL ><
Koi Cha no Osahou Komatta Toki ni wa Hoshi ni Kike! Sex Pistols
________________ "The are some things you can never get back, no matter how much effort you put in. And there are some feelings of despair, that you can never shake off." -Ciel, Kuroshitsuji