I used to lock the door when my girlfriend was in the room, but now I don't lock the door when I leave.

I want you to see him off. In love, when a man leaves the room, his girlfriend will lock the door. Leaving the door unlocked means that his boyfriend wants you to come out to see him off. Falling in love is a social activity, a process of cultivating love or mutual communication based on love, mainly the communication between the two sides.