Watatsuki no Toyohime is one of the leaders of the moon emissaries, who are responsible for defending the Lunar Capital and monitoring the earth. Despite her appearance, she has a rather tomboyish personality.

Toyohime used to study under Eirin's guidance and has great respect for her. As a leader of the moon emissaries, it is technically her duty to subdue her erstwhile teacher, but she probably never will.

There is a peach tree in the garden of Toyohime's mansion. She often reaches out of her window to snatch its fruit for herself. Her younger sister Yorihime is quick to reprimand her, but Toyohime always manages to change the subject.

Toyohime and Yorihime are both looking forward to when Eirin finally returns to the moon, but the possibility is still too far off even for a dream within a dream.

Toyohime decides to descend to earth with Yorihime and Reisen. While Lunarians hate impurities in general, Toyohime has been to earth before and apparently thinks of impurities simply as an inconvenience. Besides, her will to meet her dear teacher is stronger than anything else. She departs for Gensokyo with a gift of moon peaches in hand.