First of all, excuse my English, it's not my native language. I speak Portuguese and I'm using Google Translate. Regarding Lucy's disappearance, I discovered that to continue the story after she catches the MC and Rose having sex, there's a scene where the MC overhears the two talking in Lucy's room. The next event is her waking the MC up in the living room and accusing him of ruining everything. But for this to happen, he has to still be sleeping in the living room; May can't have moved out and given him the room yet, otherwise the scene won't play and it will freeze.