Ya'll been together ten years, you deserve a ménage
Especially if you put that BMW in the garage
Especially if you paid a couple payments on her Mamma crib

from 2 Chainz (Ft. Kanye West) – Birthday Song Lyrics on Rap Genius

Meaning

You have every right to have sex with your girl and her friend if you’re the reason that girl is living the lavish lifestyle she is, and if you’re paying for her mamma’s house.

Also; a possible Kobe Bryant reference?

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