Mamoru has slick, short dark colored hair with two small bang strands hanging over his face. His eyes are generally very lazy looking or very creepy, but can also turn much more cartoonish when excited or nervous.
He wears his restaurant's uniform, consisting of a white long sleeved shirt, dark long pants, and an apron that says 洋食の三田村 (Western Cuisine Mitamura).
Little is known about Mamoru's past. However, it was stated that he is the 3rd Generation owner of Western Cuisine Mitamura with his grandfather and father as the 1st and 2nd Generation owners, respectively.
Main article: Stagiaire Arc
Mamoru encountered Sōma Yukihira and Hisako Arato after apologizing to the customers they were not able to serve. He introduced himself as the 3rd Generation owner of Western Cuisine Mitamura before asking for the two's autographs. Moments later after inviting them in, a large wave of customers burst right in the restaurant. Mamoru was rushed doing the dishes before a second wave of customers came. He later got a customer angry after mistaking their order. When the restaurant closed down for the day, everyone was ecstatic and relieved that they managed to finish the day with little trouble. He and the staff thanked and complimented Sōma and Hisako for their exceptional performance.
On the third day of the Stagiaire, Mamoru was seen looking at a portrait of the restaurant when his dad was still the head chef. He was approached by Hisako, telling her about his restaurant's history and strengthen his resolve to save it. On the fourth day, he asked Hisako to sort the receipts whenever she is free, before being startled when she suddenly requested an emergency meeting. Concluding the meeting, he decided to adapt Sōma's idea of making the restaurant accessible only through reservation, despite open opposition from the staff. On the last day, he greeted an old patron, Shimizu, who made a reservation after hearing the news. Shimizu was happy to know that Mamoru knows his usual order. Afterwards, he listened to Hisako's explanation about the improved reservation system they would use for the restaurant.
- Western Cuisine - Mamoru is the owner and head chef of Western Cuisine Mitamura. Their restaurant also serves a napolitan which is a form of Western Cuisine.
(To be added)