Sumorai is one of the bad robots from the crashed space prison who soon turned good robot and supporting role for the rest of the series.

Story
Sumorai was originally a warrior robot, before being modified to be a domestic robot after said war. He once worked in a military base, before burning it down (on accident!). Said accident caused the rumors of Sumorai's dangerous power to spread like wildfire (no pun intended). He was promptly kept in the lowest part of the space prison.
It was unknown when he wandered into Kota Hilir, but he had a friend named Oyen-san, a small orange kitty cat.
Trivia
- His name is a combination of the words "sumo" and "samurai".
- He shares the same voice actor as trocket ( Malay dub only ).
- In the teaser, he was originally planned to be Mechabot's old friend from the space prison. But it was soon changed as seen in his debut episode with mechabot being frigthened of him.