This is a story about Rion Izumi, a petite childhood friend with a secret passion for diaper play. She's a serious, studious, and popular student council president, but secretly, she loves dressing up in baby clothes, getting her diaper changed, and acting like a helpless little girl.
One day, the protagonist discovers her secret stash of baby clothes, panties, and diapers. He's shocked but also intrigued. Rion, realizing he knows her secret, uses it to her advantage, demanding he become her "daddy" and indulge her diaper fantasies.
Despite being a responsible and serious person, Rion's sudden shift into a clingy, demanding baby girl is both shocking and exciting. She loves wearing cute baby clothes, begging for diaper changes, and even wetting herself on purpose at school. She's also surprisingly picky about how she's treated, demanding better diaper changing skills and more attention to her "baby" needs.
The protagonist, forced to play the role of her "daddy," finds himself increasingly drawn to Rion's innocent charm and the thrill of fulfilling her childish desires. Their relationship evolves as he navigates the challenges of her demanding diaper play, all while trying to maintain his own sanity.
This story is told from the protagonist's point of view, offering a unique perspective on his intimate relationship with his petite, diaper-loving childhood friend. It's a heartwarming (and slightly bizarre) tale of their evolving bond, told through the lens of their shared diaper play fantasies.