Quote from MewMan
Supernatural, Romance, Tragedy= Elfen Lied
. However, the art is kinda...(up to you)
Haha, it's not exactly sweet though in terms of similarities. (but I'd also like to recommend this too if you're open to mature seinen)
Quote from LawX
You are like the dense main character in a shoujo manga.
Quote from Crenshinibon
And you will murder someone one day, pika. If you're my daughter.