Talks to himself!

Hahaha! Vent! 
My boyfriend talks to himself all the time! I find it to be really cute but he does it so much? Usually it's just a whispering of him talking to himself or describing what he's doing as he's doing it.
Sometimes it's so loud! This one time I was in the bathroom and I was on my phone and heard what sounded like demonic whispering. So I shout at my boyfriend asking if he's talking to himself and he goes really red in the face and says no. Clearly you were and really loud because I heard it all the way in the bathroom! It sounded like he was whispering right beside me! 
I just had to get that off my chest! Can't talk to anyone else about it because I don't want him to get even more embarrassed. Does anyone else know people who do this? 
No, he doesn't have anything wrong with him.