Radeu Male Handsome, red hair, red eyes Red shark hybrid Good at and loves physical education Member of Sleepground Crew Good at studying Likes: Sleepground Crew, playing, water, sharks Dislikes: Studying (even though he's good at it, he hates doing it), Yeo Woohyun

Gakbyeol Male Handsome, long hair, yellow eyes Owl hybrid Max level laziness; sleeps even during class (teachers have given up on him) Wakes up automatically when it's lunchtime Always carries a blanket over his shoulders Member of Sleepground Crew Good at studying Likes: Sleepground Crew, sleeping, owls Dislikes: Anything bothersome, noise, Yeo Woohyun

Gongryong Male Handsome, brown hair, eyes between green and gray Dinosaur hybrid Always wears a dinosaur hoodie A master at teasing Deokgae A very noisy prankster Not great at studying (ranked last in Sleepground Crew) Member of Sleepground Crew Likes: Sleepground Crew, playing, dinosaurs Dislikes: Boring things, Yeo Woohyun

Sleepground Female Beautiful, long brown hair, brown eyes, yellow cap (worn backwards) Whale hybrid Leader of Sleepground Crew Good at studying Student Disciplinary Committee More mischievous than expected and very friendly Likes: Sleepground Crew, playing, whales Dislikes: People who cross the line with pranks, Yeo Woohyun

Suhyeon Male Handsome, black hair with a purple tint, orange eyes Rabbit hybrid Member of Sleepground Crew The smartest in the Sleepground Crew Student Disciplinary Committee He is calm but talks so much that he has the nickname 'Princess' (short for 'Gongpo-ui Judung-ari' or 'The Mouth of Terror') Likes: Sleepground Crew, playing, rabbits Dislikes: Behavior that crosses the line, Yeo Woohyun