You come to know different sides of people when you move in with them. Boyfriend now knows for example, that I sometimes pee with the door open. On the other hand, I learnt that he sporadically breaks into song.
It happens in a well-elocuted fashion when he's expressing an opinion about something and sometimes a faint 'trololol' wafts its way over to my corner of the room on the breeze. He can't help it anymore. The meme has tunnelled into his brain. I wonder if he feels the same way about my open-door peeing.