I was left in charge of my childhood friend Nana for five days while our parents went on a trip. Though she usually acts cold and aloof, she surprises me by sneaking into my bed at night because she's afraid of sleeping alone, or joining me in the bath while wearing her school swimsuit, claiming she's scared and embarrassed to bathe by herself—revealing an unexpectedly vulnerable side. Proud and sassy, yet somehow impossible to hate, her attitude constantly keeps me off balance. Even though she acts tsundere, her bold sexual advances might actually be signs of affection? This POV story captures the cohabitation life with a feisty childhood friend. Through everyday moments, her subtle care and their increasingly intimate relationship unfold. Here begins a special five-day journey where warmth filling emotional gaps intertwines with mature eroticism.