This is the tale of a tumor.
I couldn't help that one.
In reality, this story encompasses the life of Riley, a young human with a peculiar SOUL trait. In this AU, humankind sent not only the monsters into the Underground, but a disease as well. This disease, a tumor, fed off of monster magic, rendering those infected both insane and dust-thirsty. Discover how Riley deals with the Underground at the mercy of Flowey's resets while simultaneously trying both to survive and save the ones they come to care about.
New parts come out slowly
(This is my version of HorrorTale)
Frisk seems to abandon the underground. The monster try to move on but the thought of her being gone isn't a nice one. Years later a human child falls into the hell, Frisk had abandoned.