>>538433270
Because Mo Fu is an immature BPDemon who's very heavily into NTR, and he fell for Effy's sociopathic behavior.
It already happened before. After being cheated on and dumped by Appal, Effy decided to fill that void by leading on vulnerable, mentally ill, submissive gooners.
He did it with Mo Fu, Tali, Sarah, Menhera, Val, then Appal came back.
Appal rejected him again, and he seems to be back to Mo Fu, who's a very easy target. There was also something brief with Yume or some other femra bike, but I forgot who it was.
Worst one was with Tali. Led on, cucked, and dumped by Proxy and Effy.
I guess the drama with Lientri is because he misread Lientri as a potential target, and Lientri made the mistake of leaking the interaction and saying negative things about Effy.