Shuuen wo Maneku Shinryuu dakedo, Papatte Yonde Moii desu ka?

Synopsis

In the Blueforest duchy near the border, there is a city where "humans," "demons," and "gods" coexist — it's the most exciting but dangerous place in the world. Every day, Ryan, a fifteen-year-old boy who currently serves as the Duke of Blueforest, along with his beloved "wife" Rei, must face the cataclysmic dangers that can be created by a whim of the gods. One day, Ryan decides to take in a girl he rescued from the battlefield… "Is it okay if I call you 'Papa'?" The girl's name is Amadeus. She is a terrifying being known as the "Apocalypse Divine Dragon," a potential disaster in human form. However, to Ryan and his wife, who have longed for a child of their own, she is nothing more than a dearly beloved daughter they could never love enough! In other words, it's an unstoppable wave of love and affection!! "Ahhh, my daughter's cuteness has reached lethal levels!!" To protect his family and the world, Ryan, the genius mage, must become the most powerful and coolest dad! An undebatably adorable and heartwarming 'Father-Daughter' fantasy begins now! (Source: GA Bunko, translated)