Thank you for checking out the game! The reasoning for the creature appearing inside is more because it has enough power to materialize in a visible form but can't interact with you on a physical level since it's powers are weak. It is spiritually connected to the home from the outside, the connection points being the entry ways, and if you forget something open it can slowly gain enough strength to appear in it's full form. But I like to leave the logistics and theories up to player interpretation most of the time. I appreciate you sharing your thoughts!