This robot paper model is PM-10 Boss Borot, a fictional mecha from the anime and manga series Mazinger Z, the papercraft created by Anime Mania. Within the story, Boss Borot was created by three engineers from the Photon Power Laboratory and piloted by Boss and his cohorts Mucha and Nuke.
Boss Borot serve as the comic relief in Mazinger Z, a role they would continue to play through the Mazinger timeline, reappearing in Great Mazinger, Grendizer, the OVA Mazinkaiser and most recently in Shin Mazinger. The latter part of its name comes from the Japanese phrase for "crumbling" in reference to its construction from scrap metal.
You can download this papercraft model here: Mazinger Z - PM-10 Boss Borot Free Robot Paper Model Download