This story is based heavely on he anime Angel Beats, the same plot and the same characters. (only with the idols representing the characters) You're going to have to find out who the characters are for yourself. So yeah.

Summary:

Minho wakes up in a world where he discovers is the afterlife. He is invited to the Battlefront group by Yuri, who explains that it fights God. The same plot as AB although it has more adventures. :)

Characters:

Minho

Yuri

Krystal

Heechul

And many other characters.