Sarah Sullivan had seen this kind of situation many times before.
Previously, she didn't understand what it meant, but later Holly Moore gave Sarah some context.
It's a pun.
These rich kids come to the university gate openly looking for flings.
"Drink my water" is a pun that means "Sleep with me."
If a girl sees such a luxury car and gets tempted, she might take the water off the car roof. Then the passenger door opens, letting the girl in.
It's said that the water placed on top of the car carries different prices.
Each bottle type corresponds to a different price: Nongfu Spring for 500, Green Tea for 800, Red Bull for 1000...
Sarah shook her head, feeling no goodwill toward these rich kids.
Maybe it's because she's a woman herself, so she sees it through a gender filter.
Sarah feels that women doing anything for money might be understandable, even if it means selling themselves.
But for these men to openly prey in such a way is an unforgivable sin.
