college AU where Stiles stays up late to finish an essay and by the time he’s finished he’s not ready to sleep, he’s so exhausted that hysteria has taken over and he accidentally butt dials Derek and when he hears Derek yelling from his butt pocket he breaks out into laughter, and laughs for a while, trying to explain things to Derek throughout it all and Derek just sighs, though Stiles can almost see that amused smile which is more like a twitch of the lips, there but barely noticeable and they end up talking, and Derek is in bed in his loft (Stiles had woken him up when he called and he can’t go back to sleep now) and they banter back and forth until Stiles is yawning and he falls asleep while still on the phone, exhaustion taking over and Derek takes the time to laugh, hard, because Stiles snores loudly and talks in his sleep and it just makes complete sense that Stiles can’t even be quiet while sleeping and Derek listens to Stiles until he accidentally falls asleep too, and Stiles wakes randomly to see he wasted over 3 hours of minutes and he squeaks, remembering what had happened and he hears Derek say “go back to sleep, idiot” before he hangs up and then he laughs, cheek pressed into his pillow and he falls back asleep smiling