Mirai is a short and petite girl with big bright amber eyes and pale, pink, wavy hair, which is styled in a bob-cut with bangs reaching just above her eyes. Her hair is described to be "soft and fluffy".

At school, she wears a loose pink cardigan over her school uniform, and dark leggings or similar hosiery. During summer, Mirai begins to attire a vest-like sweater on top of her school uniform, identical to her cardigan in almost every aspect, apart from the obvious lacking of sleeves. 

The reason, Mirai wears the cardigan is to conceal a bandaged wound (a gash on the right forearm in the light novels/ a round wound on the right palm in the anime). The wound serves as a way to transport the blood out of her body, whenever she needs to use her ability, to manipulate blood. In the light novels, she also wears a set of bracelets to secure the bandages to her wounds. On top of that, she constantly wears a simple in appearance, golden ring, on her pinky finger, which seals her ability.

Her most distinguishable accessory is the pair of thick-rimmed, rounded, red eyeglasses that she proceeds to adorn at all times. For a short period of time, she temporarily switches to a pair of rectangular grey glasses.