I'm looking for this manga that I read many years ago but can't remember what it was called, in fact, I can only remember the ending of it and nothing of the plot. In the end the MC (I believe the MC was female) is on the school roof with a girl with looping pigtail braids. She has a pair of scissors or some sort of sharp implement, and (I think) she stabbed the MC's love interest/boyfriend with it. She's psychotic and maniacal in the end. Anything beyond that I cannot recall.

Thank you in advance and sorry for the very vague description!

Last edited by Vitiate at 4:24 am, Jan 31 2015