Ain

A masked monster wearing a purple cloak and metal gloves on both hands. In Volume 3 of the side story, he appears alongside Olivas as an unidentified monster before Ais, Lefiya, and Filvis. He continues to appear intermittently until Volume 12 of the side story, where it is revealed that his true identity is Filvis. His true form is a monster implanted with a multicolored magic stone by a doppelgänger of the "Corrupted Spirit" in the "Nightmare of the 27th Floor." Normally, he splits into two roles through doppelgänger magic: Filvis, a follower of Dionysus, and Ain, the masked monster.

Initially, as a monster, he couldn't forgive his tainted self and attempted to die multiple times, but his self-regeneration ability prevented it. He was saved by Dionysus, who professed love for his tainted self, and fulfilling Dionysus's wishes became his purpose in life. However, his heart was torn between his affection for Lefiya and his loyalty to Dionysus.

Leading the man-eating flowers, he faked his death to distance Lefiya from Knossos, even if it meant breaking her heart. In the final battle at Knossos, Lefiya confronts him with his true identity. He dispels the doppelgänger magic and faces Lefiya as a monster stronger than Revis. After a fierce battle, he expresses his gratitude while being held by Lefiya and disappears with a smile.