What is Humby?
1.
(HUM-bee) n.
An erection that won't go down when a gentleman has to go to the lavatory in the middle of dallying with a lady.
see also
(coined by Douglass Adams and John Lloyd)
"Sorry I took so long in the bathroom Elaine. I had a humby, and when it all finally came out I pissed in the potpourri."
See