He wanted the midnight shift, so when a co-worker asked him to trade, he was more than happy to accept.
"Thanks buddy, I owe ya one."
"No, it's fine. I don't mind."
He didn't.  In fact it took everything he had, not to act excited. 
An insomniac, who enjoyed having an excuse to be out so late. An alibi, according to some.
He loved the quite, sleep stricken, neighborhoods that the night gave him.  A playground of his very own.
The cooler temperatures were good refuge from the evil sweats that haunted him during the day.
With the darkness acting an accomplice, undetected he lurked the gardens of his affection. 
He couldn't think of a better way to spend his lunch break.