because he's covering an erection!
An erection and a place to put it.
An erection.
It's two tired.
When he stands next to your girlfriend and says her hair smells nice.
Because they are already covered.
Cover it in lighter fluid and throw a match at it: "WOOF!"
Drumpf Drumpf Drumpf Drumpf Drumpf...*
He wanted to work overtime.