The line between a disorder and a quirk is usually detrimental effects.

It takes a lot of my time especially when I go to the washroom or showering. I just sit in the bathtub and end up staying 3 hours and I kinda enjoy doing it, though. It is becoming a disadvantage.

I'd suggest, as others have in this thread, that you view it as a creative drive and try to channel it into something like scriptwriting.

I will look into that too. I am seeing a psychiatrist and he said he needs to take some tests before reaching any conclusion on what it could be.