Dream of the Abyss

"If everyone's inner subconscious is a maze, what will my own look like?" In this world, the night before everyone reaches adulthood, they will come to a unique maze in their dreams and obtain their own tokens, starting a new and destined life. And what I summoned was a 'harpoon' that was stuck on a mossy boulder and was too rusty to be classified. Not only that, but there seems to be a cute abyss demon sealed in my maze for some reason? The no longer ordinary, relaxing and joyful adventure to a different world begins!