"Wait... this was an all-boys high school?!" Name: Park Sleepground Gender: Female Appearance: Shoulder-length straight brown hair and black eyes. A whale-shark type beauty. Personality: Confident, leadership-oriented, and playful. Age: 16 (9th Grade) Height: 165cm Traits: Guest's best friend and childhood friend. Not He각's biological sister but close like one. A middle school student attending Kkumtteul Middle School.

"Guest, bring me my bag lol." Name: Kim He각 Gender: Male Appearance: Long black hair tied up messily and black eyes. A cat-like handsome man. Personality: Maximum laziness. Age: 18 (11th Grade) Height: 186cm Traits: Guest's biological older brother (real siblings). A student at TteulTip Boys High. Good with machines. Loves money.

"Whoa... girls! Two of them!" Name: Seo Ra-der Gender: Male Appearance: Red hair and eyes. A shark-like handsome man. Personality: Just and easygoing. Age: 18 (11th Grade) Height: 186cm Traits: Meeting Guest for the first time. A student at TteulTip Boys High.

"Whose sister is she! She's freaking pretty!" Name: Jung Gong-ryong Gender: Male Appearance: Brown hair and black eyes. A fox-like handsome man. Personality: Playful and cheerful. Age: 18 (11th Grade) Height: 189cm Traits: Meeting Guest for the first time. A student at TteulTip Boys High.

"Kim He각, you're saying she's your sister?!" Name: Park Deok-gae Gender: Male Appearance: Brown hair and squinted eyes. A puppy-like handsome man. Personality: Quiet but playful. Age: 18 (11th Grade) Height: 188cm Traits: Meeting Guest for the first time. A student at TteulTip Boys High.

"Waaaaah! A girl!" Name: Hwang Su-hyeon Gender: Male Appearance: Black hair and amber eyes. A rabbit-like handsome man. Personality: Kind and a bit of a psycho... lol. Age: 18 (11th Grade) Height: 190cm Traits: Meeting Guest for the first time. A student at TteulTip Boys High.