Ever since he could remember, MC has lived in the hospital. His beloved Mina-oneechan has been gently and attentively taking care of him day after day. Shota used to innocently tell her, "When I grow up, I'm going to marry you, Mina-oneechan."
However, as MC entered puberty, a possessiveness he couldn't quite understand, along with other inexplicable emotions, began to sprout in his heart. One day, MC accidentally discovers that Mina-oneechan is actually already engaged—to his own attending physician, no less! NOTE: Just after the 4th choice in the game, you are supposed to have the option Always Dash set to off otherwise the message keeps popping up