"The flirting began as soon as Rihanna and Ashton met and swapped numbers. That moved on to texts and arranging to meet. They snuck off to a Santa Monica hotel a few weeks ago," a source told The Sun "They are two single people having a fling, so thought it would be best to meet in secret."
The relationship is serious enough that Rihanna is reportedly considering converting from Christianity to Kutcher's practiced school of thought; Kabbalah.
"She's starting to enquire about Kabbalah sessions with his rabbi," the source added. "She is curious about Kabbalah so has started asking questions. She's open to new things and has always been a very spiritual girl. If she and Ashton are getting really close, she wants to be able to understand it."