[Kanten] Yuri and Tentacles (Haizan Senki ~miserable valkyrie~) [biribiri]

A shrine maiden bound by duty to purify the boundary between humans and apparitions discovers her sweet junior Yuuri has already been claimed by the very spirit she swore to destroy. What begins as tender closeness between the two women twists into something monstrous as tentacles erupt from Yuuri's corrupted body, binding her helpless senpai and dragging her into a slick, overwhelming surrender her clan's teachings never prepared her for. By the final page, both girls have drowned completely in the apparition's grip—swollen, mindless, and blissfully happy in their ruin.