The 31-year-old actress - who played prostitute dominatrix Gail in the first movie adaptation of the graphic novel - explained while she is keen to work on a sequel, director Robert Rodriguez needs to start filming soon or she will feel too old for the skimpy costumes associated with the character.
She said: "The last time I saw Robert Rodriguez was a month ago and he really wants to make 'Sin City 2' happen. I said, 'I understand you've been taking your time, but if you want me to wear the outfit that fits into one hand, dude. I'm not getting any younger.' "
The 'Rent' star also admitted she is grateful for her unusual looks - which are a combination of her Puerto Rican, Afro-Cuban, Native American and Irish descent - as some of her more conventional-looking friends struggle to find acting work.
She added: "I have friends of mine who are actresses, who all have blonde hair and blue eyes, tell me they think I am going to work more than them.
"One of my friends in particular - and she's a pretty big actress - said, 'There are a million girls who show up who look just like me every single day in Los Angeles fighting for the exact same job.' "