>> this is 31-year-old david demers. >> you can sit down if you want. >> oh, thanks. >> demers teacheshnology at a trade college in orlando. using the screen name audavideo, he chats online with a decoy named annie who tells him she's 14. and right from the start demers seems to know he's asking for trouble. >> well, having any type of romantic relationship with someone younger than 18 is walking on thin ice. >> the decoy tells him she had sex with her ex-boyfriend but didn't like it very much. then, like many of the men we meet, demers becomes a sex education teacher, explaining the benefits of sex in a swimming pool. >> and the sensation for you is like having sex on a cloud. >> then, a class in sexual positions 101. >> missionary is the first one. doggie style is the second one. >> and when the girl asks about group sex, he describes it in graphic detail. >> simply put, one guy has his [ bleep ] in her mouth. >> oh, geez. >> the other guy has his [ bleep ] in her [ bleep ]. or her [ bleep ]. >> oh, dang. >> i love teaching you. it's so fun. >> he sends her pictures of his penis and