My guess is Yue went with him willingly because she's gonna put him in his place, especially after seeing Gu Yu take those drinks in her place.
Still surprised by how quick our girl was to tell Lu Yang she's an omega, but she was drunk so I guess that explains it. I wonder if this is going to end up with Lu Yang resenting her or if the crush will switch to genuine friendship. Though it'd be funny if Lu Yang is still interested and wants her even after learning Gu Yu is an omega like her.