As it turns out, I found out who they are.
As far as I can tell, it's a mix of characters from Future Diary, Tales of Xillia, Love, Chunibyo, and Other Delusions, Guilty Crown, ef - a fairy tale of the two., Angel Beats! and maybe High School D×D.
Yes, I took screenshots of characters and used Google Images to search.
I must be insane.
… admire your determination…