Yui's heart races at the thought of reuniting with her brother after five years apart. She can't hide her shock at his sudden marriage announcement. The sweet and sour memories of their childhood promise, which had been buried deep, now resurface vividly. She wants to convey her boiling emotions... "You said you'd cherish me forever, didn't you? I love you so much, big brother!" Yui, the adorable sister, smiles sweetly, and forbidden love between brother and sister begins. They give themselves completely to each other, gradually awakening to pleasure. Over and over again, they engage in unprotected sex, greedily indulging in carnal desires, strengthening the bond between them...
