I've never understood the "parent(s) had debt and ran away so suddenly the child is responsible for it" bullshit that's shown in stuff like this and Hayate no Gotoku. That's not how any of that works at all. It would actually be an interesting story if this could happen in real life.
Maybe because I live in a corrupted third world country, but this is a pretty common scenario here. I mean, you could get help from the police, if your debt collector was a small time goon. If they're yakuza/mafia level, in most cases the police would be a silent audience to the whole ordeal. Either because they're on the mafia's paycheck or simply afraid for their lives. Now if you're a guy, you'll either get beaten up and left on the streets, or, in extreme cases, be killed. If you're a woman tho, you're screwed. Unless you're super old, you'll definitely be raped and/or forced into prostitution for the rest of your able bodied life. So this manga, at least to me, is pretty realistic.