Hbu
Hbu is text slang for "horny boy up." It is for exclaiming that a boy woke up horny, or is used to ask if a boy is horny after he woke up.
"How are you this morning, mom?"
"Good, son. Hbu?"
"Ew God mom that's disgusting. Why would I answer that?"

"Good morning?"
"How are you?"
"Good hbu?"
"Only because you're texting me this morning ;) "