sleep cameln.
A person who gets little sleep during the week, and then attempts to make up for it by sleeping in and napping on the weekend.
Example Citation:
"Spotted any Sleep Camels lately in your office? Sleep Camels are ultra-workaholics who go for days without resting, then power-sleep or power-nap for most of the weekend in an attempt to store up energy for the week ahead."
"News," The Guardian (London)