Helltaker - Romantic comedies

The spider girl and the random guy from Mosquito Season! Vanripper is giving cameos to his older works!
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Wait, Spider Season is the name of this movie and the book that Modeus is usually reading, that means that Mosquito Season exists as a fictional work in the world of Helltaker.
New theory; all the works by Vanripper are fictional works in the world of Helltaker and they were all made by the same person, Vanripper himself!

but how do we know Helltaker isn't a fictional work in the Mosquito season universe?