Just don't think the sword is a d-
Art by trashmasterflex

You were forced to go into the cave with the ferocious dragon after being told it is almost dead, the hole penetrating her belly with it showing the weak spot of the heart.

You needed some sort of sword. A deepest sword...

Source: Deepest Sword

While contains themes of feet and , it is entirely optional, that is if you wish to humiliate yourself, weakling.