Inthefuture,humansaredividedintoSexNegativesandSexPositives.ThenegativesgetsickiftheyhavesexsotheygotoCafeFleshtoseepositiveswhoareforcedtoperformonstageforthenegatives.Lanaisapositivewhoeveryonethinksisanegativeandshemustdecidewhethertocomecleanornot.