Aira and Rizumu discover that both were born on the same day, under the Skater constellation. After hearing this, Mion plans a surprise birthday party with help from Callings. After Mion puts on a Prism Show at Aira's request, Kyoko and Jun announce that Mion, Aira, and Rizumu are scheduled to debut as a group under the name "MARs", also revealing that Mion was also born under the Skater constellation when it appeared in the Southern hemisphere.