"He used to be so kind..." Sonoka is a little sister supporting her brother, a shut-in who has completely fallen apart. But one day, while bringing him a meal, she is forcibly dragged into his room, and her G-cup breasts are sacrificed to his lust. Ignoring her screams, her brother kneads her breasts and showers them with cum. Despite this, driven by a desperate desire to protect her brother's place in the world, she chooses to live as his "exclusive tit-onahole." Through days of repeated creampies and titjobs, her brother begins to leave his room, driven by his craving for her breasts. Even in this twisted form, it represents a hope for his rehabilitation to her. She stops resisting and devotedly accepts being his sexual outlet. A sad yet lewd story of codependency between siblings.
