In the fourth part of the CarousHELL saga, Duke tries to help Robbie understand growing up isn't scary. On a father/son vacation to a cabin in the woods, Robbie finds the Nekkomeownicon and tries to speak to his late mother. But these words are instead heard by The Leviathan and its demon horde.

Duke hates his job. He has to let kids climb on his back and ride him for hours every single day. But one brat finally pushed him too far. Duke has broken free of his ride and is on a bloody rampage of revenge. He's going to murder that kid and anyone that gets in his way.