An alternate retelling of the beginning of the original series. Mikako and Tsutomu lived next door to each other since they were little. They both attend an art school, where Mikako is pursuing her dream of being a fashion designer. They formed a club called Akindo with several of their friends. Akindo participates in flea markets, where they sell their creations—clothes, dolls, and artwork.

The protagonist, Kouda Mikako, is a student of "Yaza Gaku". Specialising in fashion design, Mikako dreams of becoming a fashion designer with her own brand. Living next to her is her childhood friend, Yamaguchi Tsutomu. Even though they have been close since they were young, they share a platonic friendship. However, Tsutomu has been gaining popularity, especially with the girls, because he seems to resemble a popular vocalist from a band and somehow, Mikako begins to see him in a different light. This is a story about how youths cope with dreams, love and friendship.

Continuing his adventure to get stronger in order to traverse deeper into the "Dungeon," Bell Cranel wanders the Orario city streets with his friends and the goddess Hestia. That evening, the city is filled with stalls and games as it celebrates the Holy Moon Festival.

Hermes, a god, hosts one such activity where participants are asked to pull a spear embedded in a crystal boulder; those who succeed will receive a special gift: a trip around the world and a divine blessing from the gods! Bell and his merry group challenge one another to claim the prize. But behind the facade of an innocent party game lies a preface for a daring quest ahead.

The anime's story will start where the third season left off, at the competition for who will open the Triple S international sporting event. Raging Entertainment's HE★VENS idol group had hijacked the competition between QUARTET NIGHT and ST☆RISH, causing chaos. However, after the QUARTET NIGHT members suggest a certain idea, the three groups aim toward a new stage, with HE★VENS swearing to get their revenge on the other two groups.