Reality TV personality Khloe Kardashian told her sister Kourtney that she lost her virginity at the age of 15.

While playing the game of "Know Thy Sister" for her website kourtneykardashian.com, Khloe confessed about her sexual life.

Kourtney said: "We are going to play a game called Know Thy Sister, a question is going to pop up and we have to see if we know the answer."

She then asked Khloe when her first sexual encounter was, and she wrote down on a white board the number 15, reports femalefirst.co.uk.

And Khloe, 31, added: "I think it was 15?"

Elsewhere in the game, Kourtney was asked when her first lip-locking session was and she said it was "a late first kiss".

The mother-of-three was shocked when Khloe asked her if it was in fifth grade she had it.

She responded: "What? Who do you think I am?"

However, Kourtney clarified and teased that while she was late to kissing she did other stuff with boys, which "made up for it."

"I remember it being a late first kiss. But I made up for it by doing more than just kissing," she said.