MUSKEGON, Mich. — A man who pleaded no contest to entering into a sex pact with his girlfriend and her 15-year-old daughter and to having had sex with a 12-year-old relative was sentenced to up to 25 years in prison.

Michael J. Fitzgibbon, 37, was sentenced Friday to up to 15 years for each of four counts of third-degree criminal sexual conduct after prosecutors said he, his girlfriend and her daughter signed a contract allowing the teen to be his sex partner for two months.

He was also sentenced to 12 to 25 years for each of two charges of first-degree criminal sexual conduct for having sex with the 12-year-old girl. All six sentences are to be served concurrently.

Fitzgibbon pleaded no contest to the charges last month. A no contest plea is not an admission of guilt but is treated the same way for sentencing purposes.

The case arose after Fitzgibbon's girlfriend, afraid of losing him while she was recuperating from surgery, allegedly arranged for the Fitzgibbon, herself and her daughter to sign a contract in June. In exchange for sex, the 15-year-old testified she was to be paid and receive privileges, such as piercings, hair dyeing and permission to stay overnight with her own boyfriend.

The girlfriend, whose name is not being made public to protect her daughter's identity, has been charged with three counts of third-degree criminal sexual conduct with a person 13 to 15 years old and is scheduled to stand trial in April.

Authorities investigated after the 15-year-old told a relative in July. The 12-year-old came forward after charges were filed.