Getting a blow job while in a
hot tub, or any other
form of water. To be defined as a blowfish, the girl's head must be completely submurged under water, except to
come up for air of course.
Girl: Wow this hot tub is nice.
Blowee:
Yeah it is, have you ever given a blowfish?
Girl: No, what's that?
Blowee: I'll show you, here's a
snorkle.