Henna - Skeletal Shark

In surf lingo, henna is "...[e]arly 80s [surf] slang meaning "you think so?". The term is "...usually used after a sentence when you're talking to someone you know well". Sentence example: "That guy just caught some major air! henna?" This definition was originally found at riptionary.com but the site seems to be down at the moment.

Here's another definition of the surfer term henna which is fairly similar:

“Henna” is a term of inquiry that amounts to, “Would you agree?” Sentence example: “Claire’s house was pretty fun last night! Henna?” -  Red Bull's Surf Slang - Board Babble

The font used is: Whippersnapper BRK

The original drawing can be seen here: Skeletal Shark