I've been debating if I should post him up here but I like that satchel too much.
Not really "original" if he was made in the character creation in MH3U but I did give him a dumb back story.

You ready to hear it? Are you ready? You ready? -BAM!-

As a kid, Rue had always loved large monsters. When he was old enough he left home to merchants trades in other regions studding monster ecology and collecting items related to them. After a couple of years have passed he visits his home village and stumbles across an old Hunter Weapons Guide [gunner vol]. It was because of this book he decides to become a hunter to get closer to large monsters and see them in action. With no hunter skills or experience, he travels to Port Tanzia to register into the guild anyways…. poor dork.