Height 178 cm (5'10") A fugitive who is on the run from the police after escaping from prison. He sneaks into Shion's house after being shot. Nezumi gets treated and sheltered by him for a night, then disappears without a trace in the morning. He hates No.6 and appears to know something about the city that no one seems to know. Nezumi is a rude and straightforward person. He has a deep hatred towards No. 6. Though deemed a criminal in the beginning, he seems to be an honorable person.

Spoiler

Which is shown when he saves Shion to repay him for saving himself back when they were 12. He is smart and quick-witted, easily able to defeat 4 officers of the safety bureau and steal their car. It is implied that he created the robot rats in his home which seem to be intelligent enough to follow instructions. It is revealed in episode 8 that Nezumi is the sole survivor of the forest people. His deep hatred toward No.6 is due to his Forest Home burning down.