This game looks like Quadrilateral Cowboy , how close this game to QC ?

Aside from the looks (and even those are subjective) Sludge Life 1 & 2 are not really all that similar to Quadrilateral Cowboy. Cowboy tends to have more apparent gameplay, whereas Sludge Life, at first glance, would seem more like a walking sim. You don't really do much, in Sludge Life, aside from tagging spots with grafitti, walk around, meet the people (and animals) of the sludge wasteland, play some games on your in-game laptop and, if you feel like it, solve some light puzzles in order to unlock endings. That's it. Terri Velman, the developer, calls Sludge Life a "vandalism simulator", and that's pretty much all you do in these games. They're not for everyone (no game is), sure, but that's what you'll be getting yourself into if you decide to get any of the titles: a "vandalism" experience that, on the surface level, doesn't have all that much "gameplay" into it, other than just enjoying how crazy and funny the world and the characters in it are.