Ghosting

Ghosting is moving through something that would otherwise stop you. When it is in effect the game shows Ghost Move among its conditions.

The game also has a setting for ghostable NPCs, which lets you walk through monsters: the in-game arrow menu’s Input entry sets it for one session, and E-Config (see controls) for good.

Walls, fenced edges and closed doors block regardless. So do NPCs that cannot be attacked: a shopkeeper standing in a doorway is a wall until it moves.