((I legit love purple-guy-the-killer AU involving poly!Abaddon and here’s a few stuff I think would happen if Ju was involved. :p
I can see Abaddon asking Ju to stay over for a bit and she’d get hear broken and such for seeing Abaddon’s lovers. Normally she’d try to kill them but she can’t because of 2 things, Vincent and giving up.
Vincent just scares her even more whenever he’s with Abaddon and Abaddon makes it worse by asking Vincent to introduce himself to Ju. She’d be trembling and on tears with the same shocked expression (Something like this -> 0-0) and she’d try to leave but I can imagine one of them stopping her and Abaddon dragging her back with his magic. Even if her room was upstairs, she’d try to sleep under the bed but Abaddon forbids her. Both Ju and Abaddon doesn’t exactly need sleep but sometimes they do sleep and eat.
I can imagine Ju slowly getting attached to Elizabeth but extremely terrified of her because every night (Or 12AM ish) Abaddon tortures and experiments on her somewhere where no one can hear her screaming or shouting. Eventually she’d lose both her wings and her weakest eye, when asked, she’d say she injured herself and Abaddon would agree.
Abaddon would probably invite Merrick over and he’d get confused with why Abaddon has 2 lovers but happy to see Elizabeth. He’d get concerned when seeing Vincent or Ju but before he could even ask if he can have a moment with Juju, Abaddon would let him leave. Merrick would probably sneak it to check whether she’s alright but she’d tell him to leave fast. Imagine Vincent and/or Elizabeth finding Merrick on the floor with a bleeding head and he just passed out.
And imagine Vincent heard something and noticed Abaddon isn’t on the bed and walks into the room Abaddon and Ju is in and he sees her tied to the wall, crying and begging Abaddon to stop and he just snaps one of her wings off. Just her scared look and reaction made Abaddon realize Vincent’s there.
The main reason he takes away his daughter’s wings is not to fly away, he takes them away because his were taken away and if he had them today, he wouldn’t feel like an outcast and would feel more loved by Vincent and Elizabeth.))