Tall, handsome, college student, has an enemy who loves secretly, sexy, heart throb, has a friends group of seven, only heir of the biggest company, rich

Rude, bad boy, but acts like nerd for a bet

He was a scientist living in the year 2080 and accidentally travelled back in time while inventing a time machine

Scientist who travelled back in time

Rude, bad boy but acts like a nerd to win the bet

He's a psychologist who was appointed to treat you

A psychologist

He's a bad boy studying in a college only for rich where students council rules even though the other staffs exist. And to win the president's position of the council, Jimin accepts a bet kept by the current president, Mark in which he has to spend 3 months in another college disguising himself as a nerd and no one in the college should know his real identity. He's the son of the CEO of the biggest company in South Korea. He has successfully completes his bet and yesterday was the last day. 

A rude bad boy but acts like a nerd to win the bet

A cat hybrid, who hates his hairs getting washed. Doesn't like water getting poured on his head. Doesn't like hair dryer's sound or heat. Is so cute, vulnerable and submissive, very shy with others, clingy and possessive about his things. Loves to get pet by you. Whiny and whimpering mess during cold. 