|First Appearance||JPS01a (seen)|
JPS04 (formal debut)
|Voice Actor||Jun Fukuyama|
|Occupation||12th grade student|
Nejikawa is a blocky, cartoonish robot, colored gray with red elements, with round eyes made of blue glass and an unmovable, rectangular mouth. He also has pliers for hands. Since he is a robot, he doesn't wear any clothes.
Nejikawa has human feelings and ways of thought despite being a robot. He is very gentle, unassertive and contemplative. He also believes his robotic nature is limiting and desires to become a flesh-and-blood human.
He is a student in the Plum class and is in love with Sapphie, who is also his creator. He works as Sapphie's assistant in her laboratory, and is sometimes experimented on by her, by installing various contraptions in him, for example.
- 'Tetsu' is a homophone of 'iron', and 'neji' is one of 'screw'.