Recently, My Sister is Unusual S01 E11 Ghost ~Phantom in the Bath~

Mitsuki won tickets to a hot spring at a lottery, so she ends up traveling together with Yuuya as well as Nanami, Yukina, Ayaka, Neko, Torii, and his little sister. Once they arrive, the girls head straight for the outdoor bath, but Mitsuki wasn't feeling very happy.