Obaa serves as the steadfast guardian and grandmother to Yuna, anchoring her granddaughter’s life on Izayoi Island during the series’ first two seasons. While Yuna’s father pursues marine biology abroad, Obaa maintains their home, blending practical care with a deep belief in yōkai and their hidden realm. Her mystical knowledge guides Yuna and Stitch through the enigmatic Chitama Forest, deciphering its secrets—including the Chitama Spiritual Stone—and bridging the ordinary and supernatural.

A mentor at heart, she advises the protagonists through trials, supports Stitch’s adaptation to human life, and nurtures his pursuit of kindness. When Izayoi’s school closes, she orchestrates Yuna’s transition to Okinawa New Town, entrusting her to cousin Tigerlily’s care. Though physically distant afterward, Obaa reconnects with Yuna and her father in a heartfelt reunion during a Christmas episode, masterminded by Stitch.

Her past, including ties to Yuna’s late mother or her own origins, remains unspoken. Her identity centers on unwavering guardianship, her bond with yōkai lore, and the enduring, if intermittent, guidance she offers Yuna beyond Izayoi.