Diarmuid’s heart raced.  He squeezed between two boulders that leaned against each other, stepping just deep enough that the sharp, upper tusks of the wild boar raging on the other side of the opening fell an inch short of contact.  Still not trusting his luck, Diarmuid squeezed even farther into the crevasse until he emerged in a small dark enclave.  Would the boar find another way in?

“Have you killed it yet?” said a voice.  Diarmuid spun around to see a delicate—beautiful, in fact—young man crouching by a ray of light.  He was carving stone arrow heads; a pile of finished pieces lay beside him.

“N—no,” stuttered Diarmuid; he hadn’t expected to find anyone else here.  “I haven’t.”

“I have,” said the youth.  He smiled a lovely smile.

“But it’s still alive,” Diarmuid said, pointing absently the way he’d come.

“I know.  It comes back.  It always comes back.”

Diarmuid cocked his head, puzzled, but the young man said nothing else.

“I thought this would be heaven,” Diarmuid said.  “I remember dying.  A boar—like that one, only—it was a hunting accident—and now it’s still here—still… still coming after me…”  He trailed off.

“And what did you expect to find after death?” the young man asked.

“Not this,” Diarmuid said.  “Women, maybe.  Well, not women,” he corrected.  “Peace, maybe.  Everlasting silence.  Or bliss.  Or even boredom.  But not the boar.”

The youth finished carving the arrowhead and placed it in the pile beside him.

“I thought the same thing,” he said, “when I first got here.  “Why have I died only to face this animal again?  Yes, it killed me, too.  I thought I would awake by the hateful river or perhaps the Elysian Fields.  But this is much better.”

“How is this better?” Diarmuid asked.  “You said we can’t kill the boar.”

“No,” said the young man, “I said we can kill it, over… and over… and over again.  We have eternity to learn how.  And that, my fellow, makes us a thousand times more fortunate than the living.”

Inspiration here and here.