Ren and Faafa are siblings who share the same body. Although they have different personalities, Faafa is known for her happy and cheerful demeanor wherever she goes. She quickly forms attachments with those who show her kindness, as seen in her relationship with Ai. However, at times, she can be emotionally unstable. On the other hand, Ren is characterized by his brashness, rudeness, and punk attitude. He enjoys picking fights with others regardless of their status. Despite this, he has great respect for Zero and eventually develops a liking for Ai. Additionally, Ren is driven to protect Aura users from attacks by human extremists. Like Faafa, he doesn't hesitate to use his powers whenever he pleases.