Sakamichi's mother is the mother of the protagonist, Onoda Sakamichi. She supports her son's cycling without really knowing what it's all about.
Sakamichi's mother has short, frizzy hair. Her eyes are often drawn as simple circles.
Sakamichi's mother is kindhearted, and she clearly cares about her son a great deal. She encourages Sakamichi to do his best and have fun even though she does not really understand what he's up to. She's just happy to see him working hard and making friends. She entrusts Sakamichi to Kinjou and Naruko when she meets them on the evening before the second day of the Inter High.
Sakamichi's mother is the one who had Sakamichi's "Mommy Bike" altered so that it would be more difficult to ride. As he was in elementary school at the time, she worried about him riding too far away from home. This plan backfired and Sakamichi adjusted to the change so he could continue his visits to Akiba.
Sakamichi's mother visits the inn team Sohoku is staying at on the night before the second day of the first Inter High. She tells Sakamichi to become strong and ride so as not to cause trouble for his teammates.
She meets Miyahara in the crowd during the third day of the Inter High when she loses her fellow Housewife Alliance members by accidentally taking the bus to the summit of the third day's goal with her. Although initially seeming to misunderstand Miyahara's explanation of the event, Sakamichi's mother somehow instantly understands that Miyahara has feelings for Manami without her saying so. Even afterwards, she does not quite seem to understand what the Inter High is, and still thinks Onoda is in the anime club, who just so happens to ride bicycles with him. When she witnesses Onoda competing against Manami for the goal, she doesn't know why, but understands that he's working very hard, so she cheers him on as he speeds by.
Onoda thinks he hears his mother, but believes she couldn't possibly be there; he thinks she would tell him to stop doing something so dangerous, and mentally apologizes to her that he won't stop until he wins.
After Inter High Edit
At the beginning of season 3 in the anime, Onoda was grilled by his mother about climbing Mt. Fuji, even when she did watch the event, after Naruko told her about Onoda being famous, she still has no idea about the event, but still supportive of him after reading the magazine.