From Strawberrie:

As a child, Joon-young was always teased because his mother owned a bar that served Americans. When he meets Hae-in, a blind girl, they become childhood sweethearts and he vows to always protect her. However, Hae-in and her mom take off one night, leaving Joon-young and his promise behind. Hae-in later meets Gun-woo, the rich son of a CEO. Among these three, a tragic love triangle begins to form...

Do the math--in a high school male dormitory room, there are four bunk beds…but five boys! Will these five hot dudes--Mi-Oh, Chi-Young, Jay, Ji-Myung, and Il-Yong--be able to make the best of the tight situation? Follow them as friendships--and possibly more--begins to develop among them!
(TOKYOPOP)

As a child, Joon-young was always teased because his mother owned a bar that served Americans. When he meets Hae-in, a blind girl, they become childhood sweethearts and he vows to always protect her. However, Hae-in and her mom take off one night, leaving Joon-young and his promise behind. Hae-in later meets Gun-woo, the rich son of a CEO. Among these three, a tragic love triangle begins to form...

There is also a Korean movie with the same title and plotline.

A collection of pure love stories.
Volumes:
1. Sunaebo
2. Sunaebo: Boy's Love
3. Sunaebo: Antiq + Sad
4. Sunaebo: Older
Details on the chapter names can be found in more info.

All Kum-Ji wants in life is to meet her favorite boy band, DDL. When she finds that the roster for the fan club is full, Kum-Ji despairs on ever having the chance to meet them face to face. Just when she believes all hope is lost, she decides to con her way into the boy band circuit by faking an interest in another band, Yo-I, and joining their fan club. Once in, she will have access to other bands, including her beloved DDL, who often plays the same shows. However, the best laid plans so frequently go awry, and her deception is very quickly discovered by one of the band members, E-Soh. E-Soh originally decides to blackmail Kum-Ji into doing whatever he wants, but he never planned on falling in love!
(Source: Wikipedia)