Rini gets a rabbit-shaped backpack for Hotaru, who is avoiding her. She then invites Hotaru to a picnic. Kaorinite is against it but Doctor Tomoe is not, and says she should go to the picnic with Rini, so she does.
Rini, Hotaru, and the others go into the greenhouse where Kenny is currently breeding a type of rose called a Pure Heart, which has healing powers. After Darien rejects Mimet, she is tempted to release her Daimon, Ubara, but Tomoe tells her that she must pick exactly the right time.
It starts to storm and hail. Mimet releases Ubara, who sucks out Kenny's Pure Heart through his mouth and eats it. Rini transforms into Sailor Mini Moon. Sailor Moon and Tuxedo Mask show up and the three of them fight Ubara. Ubara traps them with her roots. Hotaru grabs one of the roots and uses her power on Ubara, releasing Sailor Moon, Sailor Mini Moon, and Tuxedo Mask. Sailor Moon uses the Purity Chalice to transform into Super Sailor Moon, and destroys Ubara with Moon Spiral Heart Attack, releasing Kenny's Pure Heart, which is returned to him.
- First and last appearance of Daimon Ubara.
- This is the first episode in which Serena/Sailor Moon and Rini/Sailor Mini Moon appear without Raye/Sailor Mars, Lita/Sailor Jupiter, Artemis, Amy/Sailor Mercury, and Mina/Sailor Venus.