The elementary school sisters, Niina and Mana, have been waiting for their father to return ever since he disappeared two months ago, leaving behind only a note saying, "Life is an adventure!!" One day, the girls decide to check the lottery ticket their father left them as a birthday gift—and they discover they've won 300 million yen! Unaware of the immense value of the prize due to their young age, Niina and Mana set off to indulge in some “luxury” by visiting a certain shop. A heartwarming and whimsical story of two sisters and their unexpected windfall unfolds!