My Instant Death Ability Is So Overpowered, No One in This Other World Stands a Chance Against Me!, Vol. 7 (light novel) - Chisato Naruse - Bog

Leaving their growing entourage behind, Yogiri and Tomochika set sail on a cruise ship for the eastern island nation of Ent. But as always seems to be the case, things don't go quite as planned, and after attacks from pirates and the rebirth of an ancient High Wizard, they find their ship sinking with no land in sight. With the help of a mysterious ancient-dragon-turned-young-boy named Kouryu, they manage to escape the damaged vessel and just make it to shore in time. But as they continue on their journey to the Empire of Ent in search of the Sage Yoshifumi and the Philosopher's Stone he possesses, they are met with new obstacles as the twin goddesses Malna and Rilna finally begin to take measures to deal with Yogiri...sort of.