I like to headcanon Koakuma as an asexual succubus who thought her existence had no meaning until she was summoned by Patchouli and became a library assistant and it was the most enjoyable job in the world
Of Mice and Men style Touhou story in which Flandre escapes and kills a bunch of humans in the village, so they bring a mob to the mansion, wielding stakes, with Keine and Reimu and all, demanding Remilia hand over Flandre to kill, so they flee and live in hiding.
And Remilia keeps telling Flandre about how they’ll escape to the outside world and find a new home in England or France or something and that it’ll be okay
And then the humans catch up to them and Remilia realizes that she’s got no choice and has to kill Flandre for everyone’s own good
I’m an evil person