grizzlehinder

A sexual move that involves entering the subject's vagina or anus from behind, commonly referred to as doggy-style, when said subject (generally a gay male or hormonally-challenged female) has a hairy lower back and/or upper ass.

David saw Greg in a speedo earlier that day, and all seemed well with Greg's grooming situation. That's why David was surprised when, after one thing led to another, he realized he was dealing with a grizzlehinder.