It started out well - the concept of two boxers being bodyguards to a "good loan shark" is an interesting premise.
Sadly, characters who are normally / introduced as extremely smart, experienced, lethal etc. end up dumb or useless/powerless whenever the plot needs them to be.

An expert assassin not only doesn't do his job well (guy survives) but also gets jumped and overpowered by 2 guys.
An feared hitman gets sh*tfaced drunk, leaves his ID, wives photo and info in his office after he just dealt a heavy blow to an evil organization who he KNOWS know him. So bad guys do what? You can guess.
The heroes decide to get drunk and relax because... they took out two important guys from a wide net of evil villains? Villains who know their full names, specialities, addresses...? And they don't all hide in a safe house, no, they all just go on to work, private homes, drive out.

I could go on, especially with just how much this drama demands you suspend all logic and critical thinking for you to enjoy it.

The bromance between Gun Woo & Woo Jin was definitely a highlight.
The comraderie between the 'knifers' I loved as well but since there isn't any of it past a certain episode, most of the crumbs of joy i had from watching this show just went up in flames.

The overall acting and music was good, but the plot is weak and it has no rewatch value imo. A shame, because I was hyped for the show and excited to watch it.