The way she walks, a rolling gait that adds some sway to her rounded hips and a bobble to her firm butt, plus her weathered skin and salt-stained gear gives her away as a sailor even before she opens her mouth.  Her voice is likewise a bit weathered, raspy from shouting over the sounds of storms and sprinkled with salty slang on top of a Waterdeepian guttersnipe's accent.

Closer up, scanning down from her close-cropped red hair are eyes the grey of a stormy sea, and, most noticeably, large firm breasts that would be at home on a hefty hin peasant girl, all the more remarkable on her wiry frame.

That ample bosom tends to draw eyes away from whatever her hands are up to.  Her clothing appears to be chosen to increase that distraction, emphasising her chest with deep cleavage, her ass and thighs with a combination of tight and skimpy.  
 

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Gretchen Tightbottom is the name she gives, perhaps a result of pipeweed-addled parents or a bit of crude humour from the bosun who signed her onto her first ship, back when she was a nimble girl with a sudden eagerness to leave town and a willingness to learn the ropes.

Learn them she did, spending her time in the rigging, swinging between the sheets, fast fingers dealing with tangles, and a fast dagger dealing with troubles.

Now she's jumped ship to visit these shores, until the sea calls her again.

She thinks she's a tough little bitch, an attitude that might land her in trouble.
Good thing she likes trouble.
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The lights:  
Red: assume the usual.
White: RP