Kind of weird how this extremely strong guy, who probably has a fair bit of savings (he doesn't seem to need to work?), is young and good looking, never got a wife. No relationships that we know of either. Where is his family? He returned to his old hometown, but spoke to the elder and not his own relatives? What about friends? Even if he didn't make friends before becoming an adventurer (seems he trained from a very young age, since he learned swordmanship and magic and was A rank at 14) he's been in this one town for 10 years. He had to interact with someone. But no, he's wholly isolated.
Also, he's a bit of a hypocrite there with his teachings. He says how good experiencing defeat is for growth, but the only time he ever experienced defeat he hung his sword and never fought seriously again. Didn't try to go after the dragon again or anything. Just quietly retired in the outskirts to raise his three daughters alone.