Satou, an ordinary male student, was unable to confess his love to his childhood friend, Hime, but one day she suddenly announces she's moving far away. Satou chases after Hime and follows her through a gate of light into another world known as Arnulus!

With the belief that the Abyss King's armies are closing in, Alabaster suggests they postpone Satou's marriage to Nefritis and head to another country. As they're departing an Abyss King's knight makes it past the barrier and attacks Romca.

Satou trains with Marse, hoping to beat Granart in the sword duel to court her. Satou is torn between facing her fairly to look cool for Hime, and prioritizing his duty as the Ring King. However, the Abyss King's evil clutches are approaching Needakitta.

Peace has returned to Maasa and the gang are able to take a short break. Satou and Hime go on a date alone, but Nefritis, Granart, and Saphir secretly follow them. Satou and Hime are enjoying their date, but then they recall Alabaster's prior words.

Satou and his friends return to Arnulus among countless corpses of imperial soldiers and monsters. Satou encounters the Abyss King in a hopeless situation. Using the Ring Princesses' power he challenges the Abyss King in a confrontation to save Arnulus!