Colosseum

Read Manhwa Colosseum:

Criminals who are not given the appropriate legal punishment are abducted and given harsh punishments at Club Colosseum. One of the offenders that was brought in, though, looks to be a little different from the rest. He breaks out of the Colosseum and launches a retaliatory assault against it. Jihoon Ryu, a college student who enjoys hiding and covering up, is said to be a criminal for reasons that are now unclear. Discover how Jihoon, who turns out to have been a member of the Special Forces in the past, goes about his action-packed revenge plot!