Bathrooms are great for getting off. They’re locked, the odds that people will disturb you are decreased significantly, and if you turn on the water there’s the added bonus of muffling any accidental moans and groans that just slip out.
Of course, this all can be disregarded if you live in a place with a dirty or public bathroom, but if you have your own place or you’re still living with your this is an awesome, awesome thing.