In this follow-up installment, the story picks up four years later from where it ended in the initial series. Papuwa-kun, a enigmatic boy, now resides on a fresh tropical island teeming with peculiar creatures. Accompanied by his loyal maid, Liquid, and a newfound amnesiac companion named 'Rotarou,' they embark on absurd escapades while striving to outwit and bewilder the Ganma Army, Special Corps, and even the Shinsengumi in their quest to safeguard Rotarou's hidden truth.