Mashiro Shiina is a world-renowned artist with extraordinary talent in painting and illustration. However, despite her artistic brilliance, she struggles significantly with everyday life due to a lack of common sense and social awareness. She often speaks in a soft, monotone voice and maintains a blank expression, giving the impression of emotional detachment. Her reserved and minimal verbal communication often reflects her uncertainty in expressing thoughts and emotions.

Mashiro is notably eccentric, often appearing to exist in her own world. Her reactions are frequently unconventional, and she approaches situations with a perspective that diverges from typical social norms. This leads her to offer encouragement or comments that, while sincere, can confuse others particularly Sorata Kanda. She is also idealistic and highly trusting, quick to believe in someone’s potential if she sees them earnestly pursuing a goal.

Although she has received international acclaim for her art, Mashiro places little value on fame or recognition. This indifference allowed her to leave behind a successful painting career in England and pursue manga creation in Japan, showing no hesitation or regret in changing paths.

Mashiro tends to become wholly absorbed in her work, often neglecting basic needs such as food and sleep to meet deadlines. However, she is easily motivated by food, with a particular fondness for baumkuchen cakes. Despite her calm exterior, her emotions occasionally overwhelm her rational thinking. One example includes her attempt to learn how to cook as a way of expressing affection toward Sorata, a decision that confused him, as it interrupted her manga work, though it stemmed from her desire to connect with and please him.

Mashiro is frequently described as very beautiful, with a notably slim and delicate figure. Her body measurements are B79/W55/H78 cm (B31/W21/H30 in). She has pale skin, striking red eyes, and long, pale blonde hair that extends down to her waist.

Mashiro is most often seen wearing her school uniform, which consists of a white short-sleeved collared shirt, a red tie, a sky blue vest, a light magenta pleated skirt with a black stripe near the hem, white knee-high socks, and brown dress shoes. Outside of school, she occasionally appears in casual clothing, though she typically requires assistance with choosing and wearing appropriate outfits due to her lack of everyday life skills.

Sorata Kanda
Mashiro forms a deep and complex bond with Sorata, who becomes the first male friend she has ever had, as her past friendships in England were exclusively with girls. Although Sorata is frequently frustrated by Mashiro’s inability to perform basic daily tasks, he continues to care for her, and she gradually becomes emotionally attached to him. Over time, Mashiro develops romantic feelings for Sorata but struggles to express them due to her emotional inexperience.

Her affection is often shown through small but meaningful actions, such as wanting to learn to cook for him after observing Misaki’s gestures toward Jin, or seeking him out during a party to give him a Baumkuchen cake she thought would make him happy. In the final episode of the anime, Mashiro expresses her feelings with a kiss on Sorata’s cheek. In the light novel, she even claims that she cannot live without him.

Rita Ainsworth
Rita and Mashiro met when Mashiro was six years old at Rita’s grandfather’s atelier in England. Although Rita initially admired Mashiro, she later grew resentful of her natural talent. Hoping Mashiro would fail as a manga artist, Rita helped her transition from painting to manga by teaching her how to use a computer, then supported her decision to move to Japan. The two eventually reconcile after Rita visits Japan. Following high school, Mashiro chooses to focus solely on manga rather than attend college and ends up living with Rita in an apartment near Sakura Dormitory.

Nanami Aoyama
Mashiro and Nanami share a close friendship and call each other by their first names, indicating familiarity. Nanami often helps Mashiro navigate gender-sensitive matters and daily tasks. Despite this bond, Mashiro occasionally becomes jealous of Nanami’s relationship with Sorata, sometimes misinterpreting his actions as romantic. Aware of Mashiro’s feelings, Nanami eventually steps back from pursuing Sorata for her friend’s sake. In the tenth novel, Nanami and the other residents of Sakura Dormitory collaborate to reunite Sorata and Mashiro, four years after their breakup.

Misaki Kamiigusa
Misaki affectionately nicknames Mashiro “Mashiron” and shares a professional kinship with her, as both are talented artists Misaki in animation, and Mashiro in manga. The two develop a mutual admiration, with Misaki expressing that she fell in love with Mashiro’s eyes at first sight, as they looked at people in the same way. This emotional confession brings Mashiro to tears, revealing a deep respect between them.

Yuuko Kanda
Mashiro’s relationship with Yuuko, Sorata’s younger sister, is competitive and occasionally awkward, particularly due to Yuuko’s possessiveness over her brother. Although not deeply explored, their interactions are marked by tension and rivalry.

Chihiro Sengoku
Despite being cousins, Mashiro and Chihiro share a distant relationship, largely due to their age difference and Chihiro’s hands-off approach. Chihiro delegates the responsibility of caring for Mashiro to Sorata, resulting in minimal personal interaction between the two.

Ayano Iida
Ayano is Mashiro’s editor and one of the few people she turns to for guidance. Mashiro follows Ayano’s instructions closely and relies on her not just for manga-related matters but also for personal advice, such as when she sought clarity about her feelings of jealousy toward Nanami.