Peach Girl follows the life of ordinary high‑schooler Momo Adachi, who is mistakenly labeled a beach bunny or slut because of her tanned skin. In reality, she tans easily from being on the swim team. Momo falls for Toji, but she learns that he supposedly only likes non‑tanned girls, which shakes her confidence and forces her to doubt herself. She tries to reshape her appearance and personality to fit what she thinks he desires. Meanwhile, her friend Sae frequently undermines her, often attempting to separate Momo from Toji. At the same time, another boy, Kairi, harbors feelings for Momo.