Kuniko (久仁子, くにこ), full name Ashino Kuniko (芦野久仁子, あしの くにこ), is a first year student of Nekketsu High School. Her debut appearance in the Kunio-kun franchise is in Downtown Nekketsu Baseball Monogatari: Yakyū de Shōbu da! Kunio-kun. She takes over Rika's place as team manager of Nekketsu High's Baseball team. She is also Kunio's biggest fan and chases him whenever the opportunity arises. She has a rivalry with Hasebe and like her, was once a sukeban.
Kuniko also appears in Downtown Nekketsu Monogatari EX.
Kuniko is one of the characters in the Downtown Nekketsu series that is addressed by her given name.
- In River City Ransom EX, she is renamed Shel.