Akane's childhood was defined by severe illness and prolonged hospitalization, isolating her from peers and typical experiences. Amidst this loneliness, she treasured rare moments of connection, particularly a formative encounter with a boy she believed was Shougo Fujimi. This memory, including a childhood marriage promise, became an anchoring force in her life. As an adult, a family arrangement led to Akane's engagement to Shougo Fujimi. She accepted immediately, moving into his household despite their distant relationship, driven by the conviction that fulfilling the childhood promise would bring happiness. Unbeknownst to her, she had actually met and bonded with Shougo's younger brother, Shinya, during her illness – a case of mistaken identity. Enrolling at Shinya's school, Akane initially focused on proving herself as Shougo's worthy future wife. Though appearing healthy despite her past, she acknowledged her inexperience in intimacy. To remedy this, she agreed to receive instruction from Shinya, facilitated by his sister-in-law Sayumi, intending to use these lessons for Shougo after marriage. This demonstrated her willingness to pursue unconventional methods for her goal. Her sessions with Shinya gradually altered her emotional path. As physical intimacy developed, Akane formed genuine romantic feelings for Shinya, conflicting sharply with her original commitment to Shougo. She found herself increasingly drawn to him, struggling with the intensity of these unexpected emotions. This internal conflict complicated her relationships within the Fujimi family and influenced surrounding dynamics. Ultimately, Akane confronted both her true feelings and the misunderstanding about the childhood promise. She shifted her commitment from Shougo to Shinya, culminating in their marriage. This resolution closed the distance between them and profoundly reshaped the lives of those connected to their situation.