Sumi Sakurasawa is an extremely shy and soft-spoken individual who rarely speaks aloud. When she does, her voice is typically quiet and hesitant. This reserved nature is evident in her early interactions with Kazuya Kinoshita, during which she primarily communicates through gestures, facial expressions, and occasional use of sign language.

Despite her introversion and struggles with verbal communication, Sumi demonstrates a remarkable level of determination. She chooses to become a rental girlfriend as a means of challenging herself and overcoming her social anxiety. Her commitment to self-improvement is evident in the effort she puts into preparing for dates, often planning ahead to ensure everything goes smoothly.

True to her introverted nature, Sumi tends to overanalyze situations. Much of her internal dialogue involves anticipating a wide range of outcomes, revealing her tendency to worry and second-guess herself. However, this self-awareness also motivates her to grow and find ways to navigate social challenges on her own terms.

Sumi Sakurasawa has a soft and gentle appearance that complements her shy personality. She has reddish-pink hair, typically styled with a braid on the right side, and matching reddish-pink eyes. Her overall look gives off a delicate and approachable impression.

Her clothing style varies depending on the nature of the rental date, with no consistent outfit. Sumi often adapts her fashion to suit the occasion, reflecting both her professionalism and her desire to make each experience comfortable for her clients.

Sumi Sakurasawa’s decision to become a rental girlfriend stems from her desire to overcome her debilitating shyness and improve her social skills. As a first-year college student, she struggles with extreme social anxiety and has difficulty speaking even in simple conversations. To challenge herself and grow as a person, she joins the same rental girlfriend agency as Chizuru Ichinose, despite having little experience in interpersonal relationships.

Her first client is Kazuya Kinoshita, whom Chizuru personally asks to go on a trial date with Sumi to help her gain confidence. Though the date is filled with awkward silences and moments of miscommunication, Sumi tries her best relying on gestures, expressions, and occasional soft-spoken words. Her effort impresses Kazuya, who encourages her to keep trying.

As the series progresses, Sumi continues to improve through her work. Each date provides her new opportunities to challenge her comfort zone, and she gradually begins to speak more openly, express herself better, and even initiate interactions with others. Her growing confidence also leads her to form a meaningful friendship with Chizuru, who continues to support her both personally and professionally.

Outside of her rental activities, Sumi also serves as the protagonist of the spin-off series Kanojo, Hitomishirimasu, which delves deeper into her personal development and the challenges she faces while attempting to overcome her introversion.

The given name Sumi (墨) means “ink” in Japanese. Her surname, Sakurasawa (桜沢), is composed of sakura (桜), meaning “cherry blossom,” and sawa (沢), meaning “marsh” or “swamp.” Together, her full name evokes gentle and natural imagery, which complements her soft-spoken and reserved personality.