Сразу после любовной эскапады:

For modesties sake, he had struggled back into his boxers; though he had also struggled out of his black t-shirt, so I could wear it.
Something about; and I quote, "marking his territory".
I'd suggested he pee on me and get that shit over with, and he'd responded that he was very tired right that second, but that he'd give it a shot when we woke up.