An ordinary family, an ordinary life, happy parents and their children. Who doesn't dream of this? A deadly disease, slowly stealing the life of a young girl. Who isn't afraid of that? Her brother, desperate to do everything in his power to help his sister, treading a very fragile and dangerous path. Who would wish for that? There's a limit to everything, and man is no exception. Are you ready to push beyond your own limits for the sake of the blood you love? For the one who is so dear to you that you're prepared to risk yourself? Are you ready to face the reality that lies beyond? This is an edited AI (GPT-4) translation of the web novel series by Kiriko Kiri, published on a non-commercial premise, with their permission.