My Mistress (2014)

It's a long hot summer for Charlie Boyd. He's sixteen, his hormones are raging and he's just found out his mother is having an affair with his father's best friend. One thing takes his mind off his problems, the mysterious woman down the street who has visitors day and night, and has just advertised for a gardener. But she is forgotten when a tragic family event tumbles Charlie into a world of pain, a pain so intense Charlie thinks no-one can help him. He's wrong. Someone can. Maggie, the beautiful French stranger. She's a professional, and she specialises in pain. Giving it, exploring it, sharing it, all for money. So Charlie falls in love, and despite herself so does she, drawn to this troubled boy who takes all the pain she can give and uses it to heal himself. And as Charlie heals, he turns that healing back onto her, his Mistress.

Source: TMDb