This is really good, and the sinopsis really doesn't make it justice.
This is not about a bad ass mercenary, is about reconecting with thier human side, about learning that life is more than surviving. Value of family and friendship, of overcoming shit and all that.
The fact that the original bullies are and the nerd are becoming friends, and there seems to be actual character development in all fronts. MC, Sister, School friends, and surely the rich family faction too...
This is my new favorite korean web comic, right next to Crimsom Karma.