He’s been writing lyrics that will expose wack rappers.
Snakes are carnivorous reptiles that replace their skin several times throughout their life (known as moulting). The removal of the skin symbolizes the fake identities of the wack rappers.

‘Snake’ is also a slang term for a person who you think is sincere and really nice, but then turns out to be a backstabber.
“Fake lips” symbolizes the false content of the wack rappers' lyrics, the words that come out of their mouths.