Female demon slayer, the first one Lily ever saw.
Served as inspiration for her. Stole Lily's first kiss with her own. Owns a powerful black steed.
- "Nameless"-a thick-bladed tachi that exuded a chilly aura.
At the first time they met Rei had developed feelings for Lily and is willing to ride to her safety. She even proposed to Lily to become hers.