[Fuuga] Sono Tobira no Mukougawa - behind the door Ch. 4 (Fushidara na Ani Imouto) [KenGotTheLexGs]

Aiko and her older brother teeter on the edge of forbidden desire, their secret world expanding as a quiet day trip to retrieve a forgotten recorder spirals into trembling, tear-streaked surrender. She arches into his searching fingers and desperate mouth, her slick heat exposed under the open sky while she gasps breathless pleas—stop, don't, more—bound by whispered promises made just moments before. As Aiko hitches up her skirt and offers herself with aching vulnerability, the chapter closes on a cliffhanger reunion with their overprotective uncle Tetsuya, raising the stakes for whatever feverish intimacy awaits them behind the next closed door.