Early morning freak
A person who has no life and spends the night awake and then sleeps like a brick during the day. Usually young and stressed.
My neighbor stayed up all night and now he's taking a nap at 10 a. m. like it's a holiday.
She couldn't sleep because of her dumb phone and now she's snoring like a dragon.
My friend couldn't sleep and now he's taking a nap at 9 a. m. while I'm still awake.