Mairwen is a mysterious character, who has revealed little of her personal history or motivations for seeking adventure in the world. Her actions have proven her to be slightly unscrupulous (thinking little of stealing from fellow party members if particularly tempted, or murdering a pickpocket), yet loyal to her friends when push comes to shove.
What little is known of her personal history reveals that she was an unwelcome guest when raised among her Elven cousins.
Accompanied by her startlingly intelligent rat Hank, her motivation for helping the party are still cloudy.
Mairwen is one character who has not specifically spelled out a backstory, preferring to instead get a feel for the game world in order to understand how her character fits within it. As the campaign has progressed she has revealed little of her past, yet her personality has definitely come through. The most telling incident regarded a pickpocket, when informed that she could do anything to stop him she responded with a shrug, “I kill him.” The look of shock shock on the faces of the other members of the party indicated to me, as a DM, that she had succeeded in capturing the essence of a rogue…even though ostensibly on a quest for good, she has a certain ruthless efficiency that can cut through the formal niceties such as “laws” and “murder.”