(Verb) Using your anus to give someone a hickey. One achieves this by, spreading their buttcheeks, positioning their anus on a sexual (or non-sexual) partner, and oscillating sphincter flexes. I.e. giving a butt hickey.
(Noun) A hickey that was produced by someone's anus.
"Did you see Dana today? She had the gnarliest butt hickey I've ever seen. "
"Yo bro, I was giving this SDT girl a butt hickey when I realized I hadn't wiped in like...three days. "
"Whatever, they're not real people anyways."