So, I used the point-buy system (12 points, no higher than 15 without racials if I calculated that right), and here she is:

[b][url=http://www.myth-weavers.com/sheet.html#id=593746]Cecelia[/url][/b]
[i]Elf - Drow Rogue 1 TN[/i]

[b]AC[/b] 14 [b]HP[/b] 8 [b]Speed[/b] 30ft

[b]Str[/b] 8 (-1) [b]Dex[/b] 17 (3) [b]Con[/b] 10 (0) [b]Wis[/b] 12 (1) [b]Int[/b] 11 (0) [b]Cha[/b] 16 (3)

[b]Attacks[/b]
[b]Rapier[/b] +3 1d6+3
[b]Dagger[/b] +3 1d4+3
[b][/b]  
[b][/b]  
[b][/b]  

Sneak attack (+1d6 damage to someone with advantage)

Thieves' Cant

Expertise - Sneak and Sleight of Hand

Background (bare bones atm): Cecelia was a Spymaster, but her organization was scattered due to monsters. She's looking for a central base to reestablish her organization