Tagging and annotating in progress. I'd like it if you don't interfere yet. EDIT: I did what I could. There's some iM@S girls I don't know, and some Skullgirls, but I also don't know them well.
The brown-haired twintailed girl wearing an apron and holding a cake is probably Totoki Airi from Cinderella Girls. The blushing girl beside Anzu might be Kamiya Nao, while the blue-haired girl might be Hayami Kanade.