Punkasaurus is a nickname for attractive guys or girls that are of the alternative punk variety. Some add REX to the end, much like Tyrannosaurus Rex. Punkasarus rex is a cool nickname for any guy or girl or an affectionate pet nick name
"Hey is that punkasaurus going to that party?"
"That guy is so core, he's so punkasaurus rex"
"Have you met my hamster, Punkasaurus Rex?"