I'm Doing Ur Mom - It's a rude way of saying you're having sex with someone's m

It's a rude way of saying you're having sex with someone's mom and you're probably going to get in trouble.

He DM'd me, 'I'm doing ur mom, and I'm not even ashamed.'

She said, 'I'm doing ur mom, and I'm doing it in your dad's car.'

He yelled, 'I'm doing ur mom, and you're going to regret it!'