Looking for a shoujo manga

I'm looking for the shoujo manga where the heroine save a young man with blue eyes and didn't have any memories left. Turns out he is a vampire and nd the one who killed her mother/? years ago. In the past, her mother used to call him with a certain song with a piano/?. She did it so the vampire eat her instead of the heroine. In the end the heroine died. And the vampire wants to feed her with his blood so she will be a vampire too, but she refused (╯°Д °)╯╧╧

Sorry for my bad english but it's really bugging me for a while. I forgot the title and want to reread it again. (〜￣△￣)〜 please help me (๑•ㅂ•)و✧