SAN FRANCISCO -- A former bookkeeper and financial assistant to novelist Danielle Steel has pleaded guilty San Francisco to charges stemming from the embezzlement of more than $400,000 from the best-selling author, KTVU-TV in San Francisco reported.

Kristy S. Watts, 47, of San Rafael, pleaded guilty before U.S. District Judge Vaughn Walker on Sept. 24 to one count of wire fraud and four counts of tax evasion.

In a written plea agreement filed in court, Watts admitted that "I embezzled and stole more than $400,000" from her employer from 2003 to 2008.

The employer is identified in court documents only as Employer A, a woman who formed an entity known as TPA to coordinate the handling of her expenses, including household and travel expenses.

But in a separate case, Steel, under the name of Danielle Perkins, filed a civil lawsuit against Watts in Marin County Superior Court on Sept. 24, the same day as the guilty plea, accusing her of stealing more than $2.7 million.

Perkins is Steel's married name; she was married to financier Tom Perkins for about two years in the late 1990s.

The civil lawsuit states that Steel did business as TPA Co. and that Watts was controller of the company. It alleges that fraud and "continuous and repeated thefts" by Watts cost Steel more than $2.7 million.

The lawsuit says Steel "first learned of possible irregularities in (Watts') handling of bank and credit cards and money" in November 2008 and fired her on Dec. 19, after an investigation.

Watts is due to be sentenced in the criminal case by Walker on Feb. 4. Prosecutors and Watts agreed in the plea bargain to a sentence of two years and nine months in prison; if the judge gives a different sentence, either side would be entitled to set aside the guilty plea and go to trial instead.

Watts' criminal defense attorney, Anthony Brass, said, "This was a young mother. She had accepted responsibility and was candid with authorities."

Steel's lawyer in the civil lawsuit, Cecily Waterman of San Francisco, declined to comment on the case.

Watts, who is also known as Kristy Siegrist, said in the federal plea agreement that she embezzled from Steel in three ways: depositing checks made out by her employer for "cash" to her personal account; using the employer's credit card reward points to buy airline tickets and gift cards for Watts and her family; and arranging for a payroll processing company to pay her more than she was due, according to the plea agreement.

Watts said in the plea agreement that her responsibilities included bookkeeping, payroll, accounting and petty cash duties and managing some bank accounts.

Watts was accused of wire fraud and tax evasion for the years 2005 through 2008 in criminal charges filed by federal prosecutors on Aug. 19. She gave up her right to be indicted by a federal grand jury and pleaded guilty to all five charges.

Watts began working for Steel's TPA in 1993, according to both the criminal documents and the civil lawsuit.

The romance novelist has written 76 books and there are 580 million copies of her books in print, according to her Web site.