2 Books Found

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"So I remember the book starts with an M. The book has a train you need a ticket to get on and all these kids get on it, winding up on another world this almost backrooms esc area but its dark, cant see much, and theres this mysterious figure in black clothes There was this one scene where this girl was running away from home (its set in semi modern time) and the parents know of it, going to her room on the second floor to look out but has the lights on so they cant see anything at all"