A vengeful teru teru bozu-like monster called Miden is stealing all of the Cures' magical powers and memories, turning them into helpless infants, barring Nagisa Misumi and Hana Nono. They must help the affected Cures to regain their abilities and fight off this new menance.
12-year-old Oriko Seki, who lost her parents in a car accident, ended up living in her grandmother's Onsen Ryokan "Haru no Ya." With the ghost "Uribou" cohabitating with her and all the other odds, she ended up training to be a young female innkeeper. At first, she didn't like the training, but gradually felt her admiration for her title and began to train seriously. Thus, the growth of the young warrior Oriko begins.
A year has passed since Menma's ghostly return to the Super Peace Busters. Although the time they spent together during that summer was short, the five members reminisce about what happened as they each write a letter to their lost friend.