Fun Fun Factory

From AnimeNewsNetwork:
Michiru Mochizuki is a normal high school girl, when a birthday present from her friend changes everything. Her friend, Chiya-chan, takes her to a famous little restaurant known as Fun Fun Factory, and there she's served a dessert from their special menu - and it just appears, that the dessert contained an one of a kind "Witch berry" - and the other special menu desserts served that day contained 10 special "star grapes". When a girl eats a witch berry, and within the next 24 hours ten males eat the star grapes, a magic spell takes an effect - and the conditions were fulfilled. Now Michiru is possessed by an evil witch. To prevent the disaster she must find all of the males who ended up eating the star grapes and figure out a way to make the witch disappear.