The Testament of Sister New Devil: Departures

After Basara saved the demon realm, elders from the hero village hear about these events and agree that Basara has become a potentially dangerous foe. Before leaving for his home world, Basara confirms that Ramsus is actually the previous demon king Wilbert in disguise and has been secretly watching over Mio, though he shadily denies it. Once they arrive home, they see an advertisement about the opening of a new indoor water park and decide to go in order to deepen their bonds and get stronger.