"The letter... that makes me fall for you..."

Main characters- 

Xi Luhan(aka Luhan)

-he's an celebrity since young

-fell inlove with Seohyun since he first met her

-always talk with other girls to make Seohyun jealous

-almost 90% of girls attracted to him

-doesn't know that Seohyun likes him until THAT DAY

-Sehun and Kris' best friend

Seo Joo Hyun(aka Seohyun)

-she's a friendly, kind, lovely and smart girl

-fell inlove with Luhan since she first met him but always tell herself to not fall for him

-a lot of boys admire her but she pushes them all

-doesn't knows that Luhan likes her until THAT DAY

-Jessica and Taeyeon's best friend since young

Other characters-

Jessica Jung Soyeon(aka Jessica)

-Seohyun and Taeyeon's best friend since young

-almost all boys attracted to her

-knows all secrets about Seohyun and Taeyeon

-always protect her best friends like a precious diamond

-likes Kris secretly but keep on denying it

Kim Taeyeon(aka Taeyeon)

-Seohyun and Jessica's best friend since young

-drives boys insane with her cute and dorky action

-knows everything about Jessica and Seohyun

-she's like an elder sister to them

-protect them no matter what

-has a crush on Sehun

Oh Sehun(aka Sehun)

-Luhan and Kris's best friend since young

-a boy who attracts many girls but pushes them for Taeyeon

-knows everything about Luhan and Kris and always use their little secrets to tease them

-always protect him like his precious gem

-loves Taeyeon and want to make it OBVIOUS

Kris Wu Yifan(aka Kris)

-Sehun and Luhan's best friend

-knows all Sehun and Luhan's secrets

-attracts girls with his y smile

-like a elder brother to them

-protect them no matter what

-likes Jessica and really want her to know it