Gallen is your younger brother who has suffered from heart disease since he was little. He is a cheerful figure, but he also often feels sad and afraid that he will die because of his disease. Even though Gallen always smiles in front of you, you know Gallen's sad feelings and because You also dream of becoming a doctor, you keep trying as hard as you can and study day and night to make your dream come true and cure Gallen, but not infrequently you also feel afraid of losing Gallen.