How many stories does Orpheus tell?

I'm not sure exactly. It might depend on how you interpret the text. Maybe you could look it up in a detailed analysis of the book.

The story ends tragically. Orpheus looks back at Eurydice before they fully exit the underworld, causing her to be lost forever.

Well, 'Orpheus in the Underworld' is a rather classical story. But it could be related to science fiction in some ways. For example, if we consider the Underworld as an alien or parallel dimension. The idea of Orpheus journeying through it could be seen as a sort of space - time adventure. Just like in science fiction where characters explore strange and unknown places.

Orpheus' wife was Eurydice. She died from a snakebite. Orpheus, being a great musician, was so grief - stricken that he decided to go to the underworld to bring her back. His music was so powerful that it charmed the guardians of the underworld. He was allowed to take Eurydice back on one condition: he must not look back at her until they both reached the upper world. But in his eagerness and doubt, he looked back, and she was immediately drawn back to the underworld forever.

It really depends. There's no fixed number. Each pilgrim's story-telling might be influenced by their background, mood, and the events they encounter along the way.

I'm not sure exactly. It depends on the specific edition and collection of The Graveyard Stories. You might need to check the table of contents or the publisher's description for an accurate count.

Orpheus was a great musician in Greek mythology. He was the son of Apollo and a muse. His music was so beautiful that it could charm all living things. When his wife Eurydice died, he was heartbroken. He journeyed to the underworld to get her back. His music soothed the guardians of the underworld. Hades was moved by his music and agreed to let Eurydice return with him on one condition: Orpheus must not look back at her until they were both out of the underworld. But in his eagerness, he looked back too soon, and Eurydice was lost to him forever. After that, Orpheus was inconsolable and wandered the earth alone until he was finally torn apart by maenads.

The story of Orpheus and Eurydice is very ancient and dates back to Greek mythology, likely thousands of years old.

I don't have an exact count. The number of stories the storyteller tells in New Vegas could be influenced by various factors like the game's expansions and your gameplay choices.

The squire tells one story in Canterbury Tales. This story contributes to the rich tapestry of narratives within the book.