Manatsu Natsuumi is a first-year junior high school student born and raised on a small island. On the day she moves from the island, She meets Laura, a mermaid girl who has come to the earth alone in search of the legendary warrior, PreCure. Laura's hometown, Grand Ocean, is attacked by a witch who lives in the dark depths of the ocean, and all of their motivational power is taken away. It is said that if the motivational power of humans is also taken away, the world will be in deep trouble. Laura is captured by the witch's servant, and Manatsu transforms into Cure Summer to save her. (Source: Crunchyroll)

Tsubomi Hanasaki is a 2nd year middle school student who loves flowers and plants. One day, she dreams of a mysterious flowering tree that wilted, causing the sprites to disappear. When she transfers to Myodou Academy, the sprites that she saw in that dream appeared before her. The sprites begged Tsubomi to become Pretty Cure to protect the Great Tree, but she refuses. However, a sudden attack from a mysterious enemy came, and the Heart Seed of her new classmate, Erika Kurumi, is stolen. To save Erika's heart, she had no choice but to become a Pretty Cure and fight.

 
Note: Includes one extra chapter

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