The Hero Is Overpowered but Overly Cautious, Vol. 3 (light novel)

Well, this probably isn't the kind of homecoming anyone expected... After saving the
Gaeabrande, Seiya and Rista are rewarded (or punished) with a one-way trip to
Ixphoria. Due to their failure to save the B-rank world in the past, the baddies have
leveled up and plunged Ixphoria into chaos, transforming it into an SS-Ranked
Hellscape! And just when it seemed like things couldn't get any worse, Seiya falls
victim to a class-changing curse! Now the Overly-Cautious Hero must save this
impossibly difficult realm as...a playful piper...?