Hey Feademon, the game is listed as 3 players because it's based on a story with 3 people but I've seen it played with as few as 2 and as many as 5. You just need to change up the amount of cards you draw.
You could totally play it solo. Just draw the cards and answer the prompts like you are the only one to receive this visitation and skip any cards that are about the group of you.
Cheers