A German man pretended his car had broken down to dupe local residents into letting him use their phones to call sex hotlines.
At least four women have complained to police in Bad Urach after the man, said to be in his early 40s, used their phones.
They thought he was calling out breakdown services when he was actually calling premium rate kinky sex lines for up to 20 minutes at a time.
One victim, who asked not to be named, told police: "It was raining and I felt bad that his car had broken down and so let him in to call the breakdown services.
"But after 15 minutes he still hadn't come off the phone and when I went to look he was red in the face and was obviously excited about something."
She added the man then hung up, ran out of her house and sped away in his car.
"When I pressed redial someone called Jasmine answered and asked what she could do for me and on my next phone bill I found he's run up almost £40 on the call," she said.