Usagi Tsukishiro attends the same school as protagonist Pochita, serving as a junior member of the plant section alongside him. Her appearance features light bubblegum pink hair tied with a ribbon on the left side, square bangs, and dark crimson eyes, though alternative sources note shoulder-length pink hair and matching pink eyes.

Before Pochita's transformation, she frequently teased him while concealing genuine romantic feelings, establishing her core dynamic of masking affection with outward provocation.

Her name holds layered symbolism: "Usagi" means "rabbit" in Hiragana, and her surname "Tsukishiro" combines the kanji for moon (月, tsuki) and castle (城, shiro). A distinct sensory detail associates her with the fragrance of anemone.