Hellmouth

In Ostwind, Kansas, three strangers—

a "brainless" wizard with an affinity for thread magic,
a "heartless" lich imprisoned thirty years for murder,
and a "cowardly" human with the rare ability to see magical things

—have ended up living together in the sentient, ever-shifting Gray House. This place was built to contain the horrors that leak out of the Hellmouth, a portal to the hellish space between our mundane Earth and the magical otherworld, but someone must still ensure that nothing makes it out of the house.

This is a massive inconvenience for the housemates, but they will make it work, even when the past returns to make their job harder.