Around 40 Boukensha, Densetsu to Naru: SS-Rank no Musume ni Kyouka saretara SSS-Rank ni Narimashita

Synopsis

One day, Wollfe, an average adventurer, is entrusted with a mysterious baby. Through the retirement funds Wolffe has, the girl—Reminia—quickly grows to be a strong heroine and is called to serve in the royal palace as a "woman of valor." Worried about living so far away from her father, Reminia increases all of Wollfe's physical attack, physical defense, magical defense, speed, and auto-recovery stats to MAX. It's then that the success story about a common old man who becomes a legendary adventurer begins! (Source: Flex Comix, translated)