Thrill of the Night
"xander, i appreciate the fact that you're concerned for buffy and her safety, but lashing out upon me or anyone else really does not help the fact that this hellmouth now stands unguarded, leaving sunnydale defenseless.
COMMISSION HYPNOTOAD BUFFY IMPULSE
In a town built over a hellmouth, it frequently did. i didn’t take it personally. “yes. yes, of course. come on in. i just put tea on.” “warning acknowledged.”
SHIFT 002: The Devil's In The Details
"but i'm pretty sure we're going to the one with the hellmouth above it." "that... that would most likely be correct." tex conceded as he adjusted his goggles. "wonderful!" kickaha spoke up gleefully.
Part III: Escape
A timer ticked, counting down until the hellmouth would close again and she'd have to push the button a second time, making her directly responsible for the death of the cube. if it was alive. even if it wasn't...
Misplaced Legends, Reign of the Dragon King: Chapter 4, Dawn's Calling
"kilgair the bloody, lord of hellmouth?" the dragon asked, sounding startled. "you know him?" "know of him. his name is .. well known among dragons. he was the first pact breaker." "how do you mean?" gavin asked.
Saloon Knight
"hellmouth caverns has been a hot bed of weirdness for quite sometime. not all houngans are bad but she seems like she goin' for bokor. so that would be a perfect place fer her to set up shop."
Ghostbusters: Regenesis AU - Skin Deep V2
"they say the hellmouth housing bubble burst already." he shrugged. "i wonder how gray and dakota are doing..."
Mouthing Off
Chris had been born on the wrong side of the tracks and he'd had to seek refuge in the progressively worse sides of town until he'd wound up in an apartment situated over a literal hellmouth.
The Calm
"well, it first started when we heard that the humans there had discovered a hellmouth. lily and some of her mages went to investigate while i prepared to evacuate my children and family to safety.
Chasing the Unicorn - PART 8: ANOTHER PLACE
His eyes through his visor as the dust cleared -- and cithara _screamed._ up from the earth had torn... a _thing._ beneath them the ground shifted, settled -- collapsing away in places, the remaining walls of the cathedral fell away into the smoldering hellmouth
The Island of Dr Everhardt
Sometimes eli awoke in the dead of night, having had nightmares involving a hellmouth ripped open beneath the island. that the beasts were demons. unholy things whose tide could never be halted, until he was drowning in a sea of corpses.
La Curandera IV: The Last Crusade
The curandera had only been helpless, truly helpless, a small number of times in hir life, but the last few weeks of hir pregnancies definitely trumped the most dangerous, hellmouth-yawning, soul-corroding battles of hir long, long life.