Kanon...?

How about the servant, Kanon? He has no ties to anyone, so he should work.

"Hmm... Works for me," Eva decided after a short bit of consideration. "Are you okay with that, though, Predecessor?"

"... I refuse," the Predecessor Beatrice muttered with a sidelong glance, crossing her arms. "Kanon is my veto."

"Why the hell- Oh. Oooh, I get it it." Eva raised an eyebrow at the other witch. "You and that kid have some bad history somehow, right? Well, for my part, I'm actually okay with this. Somehow, I get the feeling that Kanon serves that witch like his furniture. There's no reason for me to play with a handicap like that. Come on, Player, choose someone else."