A man who only recently turned 18 is accused of sleeping with a 13-year-old girl.

Robert K.C. Alonzo was arrested Tuesday on a Level 3 felony charge of child molesting, according to the Elkhart Truth.

Officers were informed by the mother of the 13-year-old girl that Alonzo had slept with her daughter on Aug. 13. When questioned, the girl admitted she went over to Alonzo’s on his birthday and had consensual sex. Alonzo and the girl only knew each other for three months, and he knew she was 13, according to court documents.

Alonzo reportedly admitted to sleeping with the girl. He’s been booked in the Elkhart County Correctional Facility on $75,000 bond.