"Look, this child is being auctioned off and I am trying to save him!"
Hayden was a closet pedophile working as the principal of the Mark Twain Elementary School, where he had great access to children. Not much else is revealed about his personal life, other than that he has a wife and three children.
The BAU begin investigating Hayden after visiting Kevin Rose, a.k.a. "Hugz", a young boy posting child pornography of himself online for money, in search of an abducted boy, Dustin Powers (then only known as "Peter"), from an online auction. They pick Hayden's IM username, "mehtevas" ("save them" spelled backwards), as he is local and had sent him a link to the auction. They have Kevin set up a meeting, knowing Rawlings, a need-driven pedophile, won't be able to resist such an opportunity. After being identified outside the school where he works, Rawlings is arrested by the BAU.
When questioned about him sending the link to Kevin, Hayden feebly claims to have sent it in case Kevin knows him so he can save him and Kevin. After Reid and Elle find and unlock his laptop, they find a large collection of child pornography. Hayden makes a futile attempt at claiming it to be research for a book he was writing. When informed that the possession of the images is enough to earn him a 100-year incarceration in a federal penitentiary, he requests to make a deal, but is turned down. When asked, he confesses to making an $8000 bid for Dustin, the highest bid at the time. He begrudgingly gives them the access code to the auction chat room, allowing Agent Katherine Cole to post a request to "inspect the merchandise". Unfortunately, the auctioneer, Michael Earlson, sees a news report about Hayden being arrested and temporarily shuts down the website.
Rawlings is a need-driven preferential pedophile whose type is young boys. Preferential pedophiles are very particular about their preferences and actively hunt children, usually taking jobs that give them access to them. Rawlings had a particular fantasy that he was trying to "save" his victims, which is what he thought he was doing when he tried to buy Dustin. This is also shown in his screen name mehtevas, which is revealed to be "save them" spelled backwards.