Ikumi has short blonde hair with an ahoge, or a strand of hair that stands out, brown skin, and turquoise eyes. However, she has green eyes in the anime. She also has a noticeably curvy figure and large breasts, which she often shows off through the outfits she wears.

Unlike the rest of the students who wear standard uniforms depending on the season, she wears a slightly modified summer Tōtsuki uniform that exposes her cleavage. She also always wears a choker in all settings. Her cooking attire consists of a bikini top, short fringed shorts, two leather wristbands, and an arm sheath for her cooking knife. She also wears a Bōsōzoku jacket on some occasions, at the recommendation of Kanichi Konishi.

In more casual settings, Ikumi usually wears a crop top or sometimes a regular shirt. For a swimsuit, she generally wears a dark camo-style bikini.

Her measurements are: bust 90 cm, waist 57 cm, and hip 88 cm (35-22-35).

Ikumi was raised under a notable house, the Mito family, famed for their influence in the meat industry. As such, she flaunted her abilities and status to those she considered lower than herself. She has a fiery, combative personality and shows great pride in her skills as a meat expert. She is also a bold individual and is not above using intimidation to get her way. Much of this stems from her father, who told her to discard her weaknesses associated with being a girl since the Mito company needed a strong individual to be its successor.

Behind her tough exterior, however, is a softer side that emerged after eating Sōma’s Chaliapin Steak Don. Deep down, she is a kindhearted individual and becomes much friendlier, especially towards Sōma. She initially disliked being called Nikumi but quickly changed her mind once Sōma said it sounded cute. Only those particularly close to her are allowed to call her Nikumi, including Sōma, Kanichi, and the Polar Star girls. Ikumi has a mild crush on Sōma but is too shy to admit it. When flustered, she sometimes acts violently when someone calls her out on her concern for him. She is more than willing to aid Sōma whenever he asks for her help. More often than not, however, Ikumi misinterprets his requests, thinking he asked her alone for assistance, only to find others involved. Nevertheless, she provides all the knowledge and support she can give him when asked.

Ikumi is shown to be a very fashionable person. She owns a wide array of different bikini tops to wear while cooking and has a distinct sense of style, especially when going out in public. Her clothing choices also reflect her overall lack of modesty in showing off her body; her outfits almost always expose her midriff and cleavage.

Ikumi was born into the Mito family, which founded its empire on selling and distributing meat across Japan. A defining moment in her childhood occurred on her ninth birthday when her mother gave her a teddy bear as a gift, which made her very happy. Unfortunately, her father destroyed the bear and told his wife never to give Ikumi another gift like that again. He then told her to let go of any weakness and become strong and only strong as the successor of the Mito family empire.

Ikumi took her father’s words to heart and became an expert in the field of meat. She later applied and was accepted into Tōtsuki Culinary Academy at the middle school level. Sometime before entering high school, Ikumi was recruited by Erina Nakiri into her faction because of her extensive knowledge of meat. Ikumi championed Erina and won various Shokugekis that resulted in the disbanding of numerous clubs deemed “unnecessary” by Erina. Among the many clubs to be disbanded was the Don RS, which Erina tasked Ikumi with eliminating. The club was on the verge of disbanding until a certain individual decided to pay it a visit.