I'll Put it your ass, like i put in your mum
This is when someone is serious about giving it to you, and they're not holding back. The mum part means your mom is probably in on this whole thing.
I'll put it your ass like I put in your mum, and your mom said I could.
You took my spot, so I'll put it your ass like I put in your mum.
You're gonna wish you were my mum when I'm done.