James Dew, 43, of Murrells Inlet. faces a charge of Criminal Sexual Conduct with a Minor.
Horry County police responded to Waccamaw Medical Center on Sunday on reports of a sexual assault.
The 15-year-old victim told officers Dew had been sexually assaulting her since February, mostly when her mother and family were not home.
She said it started with him touching her breast and buttocks, but he forced sex on her twice.
The mother called police after she walked into her daughter's room while Dew was forcing intercourse with the teen, according to the police report.
Dew denied the assaults, and said he was just "horseplaying around" with the victim, the report says.
He was booked into the J. Reuben Long Detention Center on Tuesday and is being held on a $15,000 bond.