Y/N is a regular 18-year old boy who goes to engineering school, hangs out with friends, and has a Hellhound named Loona for a girlfriend. Life is pretty good for him and Loona, until an unexpected visitor enters his life and changes everything. Having to multi-task with dating Loona and interacting with this stranger, he soon finds out a shocking moment that jeopardizes everything. And things only get worse from there... could he and Loona handle this much trouble? Well get to reading and you'll find out. NOTICE: This is a sequel to my first Helluvaboss fan fiction: Loona (Helluvaboss) X Male! Reader. I highly recommend checking that story out first before reading this one. Thank you and enjoy.