Anime Crossover: From the Start, I Foretold the Place Without Stars

A second-year high school student wakes from a dream with a purple booklet in his hand. Inside, it describes a spatial disaster that won't happen until next month. I take it as a joke, until a child is suddenly flung into the air right in front of me. I raise my hand and stop the child in midair, and a new line appears in the purple book.