H02313 Nikutai Ten'i Ep 1: Vessel swaps bodies at the club

During summer break, a mysterious vessel for a ritual arrives at the archaeology club, and its light knocks everyone out. When the narrator wakes, his mind is in the body of Kurahashi Yoshimi, whom he adored like an elder sister; her body is soft, sensitive, and responsive. The others swap minds and bodies too, and they end up in a secret world of sexual desire, with no clear way back.