The village elder (or central NPC) will tell you that the path to the Demon Castle is blocked by a magical barrier in the east. To dispel it, you need to find the Earth Talisman .
Do not fight. Hide in the closets along the left wall. Wait for his footsteps to fade to the far right, then run to the Northwest door . Use Demon Sense to see his red footprint trails. demon boy saga walkthrough guide