Ikusa Otome Valkyrie 2
Japanese title: 戦乙女ヴァルキリー2
Type: OVA
Episodes: 3
Source: Visual novel
Genres: Fantasy, Supernatural, Hentai
Studios: T-Rex
Duration: 29 min per ep
Rating: Rx - Hentai

Leia is a valkyrie. She is captured by Duke, a boss of a monster group, and just when she is about to get executed, Aaliyah, an another valkyrie, appears and beats up all monsters. She tells Duke to free Leia and he does so. But Leia suddenly robs Aaliyah of a silver ring, which gives Aaliyah power, and runs to Duke.... Aaliyah loses her power and finally gets captured.... Like this, Leia and Aaliyah become their sex slaves....

(Source: ErogeShop, edited)