TW: non-con, tentacles --- This is the story of a defeated sister who is toyed with by an evil spirit she is supposed to exorcise before being sealed into eternal torment with her own stolen ability.<br> Kind and gentle, Sister Thistle has sealed many a phantom with the white coffin she bears.<br> But her kindness has also bred enmity. Tricked by the guise of her senior sister, she falls into a phantom’s trap.<br> Thistle desperately struggles to dispel her binding against the phantom that can steal the sisters’ power by bringing them to orgasm, and yet…<br> On the precipice against the relentless assault, will she be able to prevail and “Seal” this phantom..!?<br><br> Even among the sisters who specialize in the practice of exterminating the monsters that are the phantoms, there is a maiden named Thistle with the rare sacred art of "Seal". She accomplishes her mission one after another, all the while bravely saving her comrades who are in peril.<br> However, on one particular mission, she is knocked unconscious by a strong phantom possessing her comrade's body.<br> Taken to a run-down house, Thistle is bound by the phantom who stole her comrade's sacred art of “Bind”. Thistle must now bide her time until she can analyze and dispel her binding, all the while the phantom begins to tease her, telling her of their ability to steal women's power by violating and bringing them to orgasm.<br> Struggling against the unfamiliar pleasure and driven to the brink of climax several times, will Thistle be able to free herself before she is violated…?