@alacaelum i think the soft nature of Little Mo will allow her to get away with her bullshit with ease.
Remember that the last time she fucked Mo over by having him stuck with a cat spirit, was after he agreed to cooperate with her, which only happened because she fucked him over by stealing his other spirit when she already had one, which got him lynched by the leaders and in the difficult position of having to get one, which seems is something she has been doing for a while.
So even after she has done him dirty plenty of times before, Little Mo still chooses to give her a chance, and that's part of his character it was the same with Guangjin, he cheated Mo out of his chances to become an inner disciple, but after talking it out a bit he forgave him.
So it doesn't really takes much for Little Mo to just let things be forgiven after people screw him over, i think he is not holding any grudges.
But it is more because Little Mo is a pushover rather than Beibei being a likable character, she is feeling sorry for having him stuck with a cat, but has yet to reflect on all the other shit she did to him.