Han Aerin

Never give up on your life. When it comes really hard and you feel like want to kill yourself, remember that your body consists of billions of cells. When you end your life that stupidly, remember that you've killed numerous life. So be courageous enough to appreciate life. 

19, as known as Allene, sometimes an introvert, a bookworm, friendly but mysterious, she often acts it cool like there's really no problem in her life while actually she hides everything to everybody, coming from a broken family.

Kim Jongin

Who cares about what people think about you? Enjoy your life at the moment. You're the one who live your own life, so don't let anyone interupt and control it.

19, as known as Kai, a born-to-be badass and playboy, incredibly rich and extremely famous among the town cause he's the son of Kim corporation, has that gargantuan confidence and his smirk kills.

Park Nara

A girl should have two things in life, beauty and money. Life's about beauty and money, and it simply means no beauty, no life, no money, no life. 

19, called Nara, so-called goddess, has numerous fanboys and she's coming from a well-loaded-money family, greatly beautiful and y, two faced lady and lacking of inner beauty. 

Oh Sehun

Life's simple. Live it and love it. 

19, called Sehun, a mood booster, very protective and caring when it comes to his beloved ones, emotionless according to most people and reticent, he can be very talkative, childish and dorky.

EXO

Basically, a group of boys who has thick-wallet with their romeo-faced and zillions of fangirls.