A substitute teacher in Kentucky was arrested earlier this month after allegedly exposing herself during a video chat with an underage student as part of a plan to meet for sex, authorities said. Krystal Sims, 30, of Cave City, was arrested on Oct. 2 following a tip that she communicated with the boy to arrange a sexual encounter. Deputies interviewed the student, who said he met Sims while she was working as a substitute teacher in his class and that she accepted a friend request on Snapchat. The boy told investigators he and Sims began discussing plans to meet in Cave City for sex on Aug. 22, during which he showed deputies a recording of a call in which a female voice can be heard asking if he was coming to meet her. During an interview, Sims admitted to being the woman in the call but claimed she only agreed to meet the student to allow him to apologize for his behavior in class. Sims is charged with unlawfully using electronic communication to solicit a minor for sexual activity and was released on a $25,000 cash bond, scheduled to appear in court Wednesday.