Three years have passed since he left his parents. Yuu went to a boarding school to let go of his feelings for his stepmother, Yuka... But on the day of his graduation ceremony, he saw her running up to him with a smile. He felt the hidden feelings well up again. That night, when Yuu saw her get drunk after celebrating with just the two of them, he took her back to the hotel... Yuka, who was aware of his feelings, said, "This is your congratulations from your stepmother on your graduation," and gently pressed her lips against his. Guided by his stepmother, he took another step towards adulthood.