I discussed it with this girl, and this is what she said
She said, "Lay down baby, baby, rest your weary head up"
When he tells the girl how weary of it all she is, she tells him to sleep with her, to ease the pain.
This girl could be a metaphor for his inspiration to start singing instead of rapping. She tells him that rap is starting to get messed up, so just start singing and express yourself.
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