Kousoku Otome no Seikatai
拘束乙女の聖歌隊
A girl named Kujou Hina is known for her singing abilities. After witnessing two unknown girls perform, she receives a choker from them that allows her songs to expel evil spirits. She questions the identity of the two girls and why she was selected for this power. As she seeks answers, she encounters others who also possess similar abilities.