I just can't stand the bootlicking protagonists in stories like this. They're always portrayed as "kind," but it just comes off as pathetic naivety to me. His family literally laughs in his face, treating him like he's subhuman, and his reaction is:
Thank them for what? Dude could get kicked in the balls and still lick their shoes clean for daring to sully them with his filthy self. This is just too Japanese for my taste. He's the type of person who'd overwork himself to death for a shitty company, and then thank them for the privilege.