Man bans sister from apartment after she has BF stay over while housesitting.

There are few things that elicit an immediate "ew" quite like being confronted with the fact that your siblings are also adults who do the dirty.

On a logical level, there's nothing gross about it - it's completely natural. But on a personal level, most people don't want to go there mentally or hear much about that aspect of any family member's life.

At least, that's certainly the case for the OP of a popular AITA post, where a man asked if he was wrong for banning his sister from the apartment.

He wrote:

AITA for banning my sister and her boyfriend from my apartment after they had s*x in my bed?

I (28M) had to travel overseas for a couple weeks for work-related reasons. My sister's (19F) college is nearby, and she offered to feed my cats and water my plants while I was gone. I said sure thanks, and told her she was welcome to stay there while I was gone, since she lives in a dorm.