Nice gif for the intro. Anyways, I should have probably mentioned this before but Character A and C are both female and Character B is male. Granted, Character A and B can be either or and even agender, but character C would be ideally female.
I have tried to do this several times before so I have a Character A and C worked out, but you can do one of those if you would like. Just tell me what you're most comfortable with.