Hello everyone! I was hoping somebody could help me remember the title of this shounen manga. ;w;

The main characters are twins, a girl and a boy. During their birthday, 18th I think, the family members gathered and the two were shown something. This thing made the girl go crazy and she killed most of the family members present. The remaining people went to hunt her down so she left the house but her brother was left there.

I'm sorry, this is all I could remember. Please heeelp. Thank you! ;w;

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Hello there! Would you please give the hungry hams a quick click? :3

Ayashi no Ceres?

Yay, that's it! That was really fast. Thank you. ><

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Hello there! Would you please give the hungry hams a quick click? :3

No prob.