This is a Naruto and Goosebumps crossover.

Long ago, a reclusive author created monsters before choosing to lock them away. Later on they were unleashed briefly before once again being sealed. Millennia later, a young sage unwittingly released them before banishing the nightmares like so long ago. Now once again, a young child striving for recognition releases them, and upon doing so changes history forever.

How ugly is Sakura Haruno's mask? It's so ugly that it even scared her one friend to death. So terrifying that even her friends are totally freaked out by it. It's the best Halloween mask ever. It's everything Sakura hoped it would be. And more. Maybe too much more. Because Halloween is almost over. And Sakura is still wearing that special mask...