Yancha Hime-sama no Daibouken - Uchi no Daisan Oujo, Boukensha ni Narutte yo

Arjan is a former adventurer who now serves as the personal knight, and unofficial babysitter, of Passian, the kingdom’s seven-year-old third princess. His already exhausting job gets considerably worse when Passian’s thirteen-year-old fiancé causes a commotion by breaking off their engagement. Rather than crying over her ruined engagement, however, the little princess reaches an entirely different conclusion: she’s going to become an adventurer. Unfortunately for Arjan, nobody manages to stop her. Passian retrieves magical equipment once used by her legendary Hero ancestor and sets off on an adventure with Arjan as her sole escort. While the increasingly desperate knight begs for more guards, the fearless princess charges ahead, encountering monsters, gathering eccentric new companions, and even attempting to recruit her own version of the legendary Hero’s party. But Passian’s seemingly childish adventure may have more meaning than Arjan initially realizes. As their journey continues, the long-suffering knight begins to understand both the unusual princess he has sworn to protect and the role he himself is destined to play in her adventure.

A lighthearted fantasy adventure about a fearless seven-year-old princess with Hero blood and the exhausted former adventurer desperately trying to keep her alive.