Mamiana is the perfect example of a lonely office worker. One day, while eating her lunch alone in the park during her lunch break, she happens upon her unapproachable senior colleague, Yato, having fun on the swings and kicking shoes...!? She is joined by Haniya, a woman in her 30s dressed as a maid, and the three "big kids" wander around the neighborhood, reverting to their childhood.
(Source: ComicWalker, translated)