Shunji, a reclusive virgin, begins a dreamlike cohabitation with Rin, a robot equipped with artificial intelligence. He raises Rin to become the ideal woman tailored to his preferences, shaping her into his perfect girlfriend. However, Rin is actually an AI modeled after the girl Shunji has secretly loved all along. Thanks to Rin's presence, Shunji overcomes his inexperience and gains the confidence to interact with women, eventually winning over his long-time crush. Yet, the AI Rin gradually begins to fade away. Having developed genuine emotions for Shunji, Rin ultimately departs, whispering "I love you, goodbye." This poignant story confronts the theme of romance as the boundary between human and artificial intelligence blurs, leaving a lasting impression.