This is a very simple and easy quest, your best bet in order to get this quest done is to stay at the Inn until morning. When you set out for the Misty Ravine head to D/5-1/4, automatically you'll be prompted that you see a fog monster! So gather your strength and step forward into the dead end and check it. Suddenly you realize that there wasn't a monster at all it was just the way the light was reflecting in the fog of the Ravine.