Met a mysterious Mariner NPC..

[Happy Birthday!]

On my first save, I built up the bridge to the East side of the beach fairly early on, within the first week.. and I met a character there that I have yet to meet a second time. His name was "Mariner", looked like an old rugged sailor type of person similar to Willy, and told me this:
"I've got this old amulet... I don't think you're quite ready for it."

That's all he said, that's all I could get him to say and paid him no mind until I realized he wasn't a person who lived in town and was never there again.

Anyone know about this mysterious man?

[Brigandine]

He is instrumental in getting you a wife/husband.