Yeah the hug is a check to know which MC personality she is talking with.
There's the possibility that the MC can be the second personality for all we know, the girlfriend is obviously in love with B-1 and they are trying to get rid of the MC.
One of the interesting plot point of this manga is that the MC when get shocked touch his ear, but how many time have we the readers watch him touch his ear when he is shocked? We maybe seeing the view point of both personalities.