All the girls wanna play Baywatch
Baywatch was a famous TV show about sexy beach life guards. Kendrick is saying that the girls are playing a Pam Anderson as they dive into a pool of liquor.
All the girls want to save him, cuz that’s what (symbolic) lifeguards do.
A poetic play on how in Baywatch the lifeguards need to resuscitate people who have drowned in the water. These girls drink a lot, essentially drowning in a pool full of liquor, and then receive mouth to mouth from some dude or vice versa.
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