How did f(x)'s Victoria make Sulli cry?

On a recent recording of 'Strong Heart', f(x)'s Victoria shared a cute story about fellow member Sulli. Victoria has a very flexible body, and she even sleeps with her legs wide apart as if she were doing the splits. Sulli wasn't aware of this, and so when she woke up one morning and saw Victoria posed in that manner with a strange expression on her face, she started to cry. Fortunately, Victoria explained the situation afterwards, and the two became close friends. A representative from 'Strong Heart' expressed, 'Victoria didn't have any experience in dancing, but because of her incredible flexibility, she went to a very famous dance school. During the recording, everyone was surprised at her flexibility.' For additional details, be sure to check out the full episode, set to air on December 14th. Source: SPN via Nate