Felton is a prison guard of Slabside Maximum Security Prison.
After Oliver stabbed Officer Dunbar and several other guards at Daniel Brickwell's fight club, the federal government sent Felton and several other guards to reform the prison. Felton ensures that there is less yard time, cell checks every half hour, and that the guards who took part in the fight club are kept in line.
After Officer Dunbar was stabbed to death multiple times in the showers last night, Felton immediately blamed Stanley Dover for it since Stanley was the last person to see Dunbar alive. Because of this, Felton and two other armored guards arrived to Stanley's cell to take him down to the hole as punishment for what he has done. Oliver secretly investigated the scene where Dunbar was killed and found Turner's blade at the scene, deducing that Ben Turner killed Dunbar because of Dunbar refusing to work for Brickwell any longer. Oliver informed Felton about this and Felton had the guards examine the blade to find Turner's fingerprints on it. Because of this, Felton had Turner detained in front of the inmates, taken to the hole, and released Stanley. However, Felton was right the first time about Stanley killing Dunbar since it was Stanley who planted the evidence there.
Later, after the FBI agreed to release Oliver because of a deal that Laurel Lance made with them, Felton arrived to Oliver's cell to inform him that he is being released even though he is a pain in the ass. When Oliver realized Ricardo Diaz was in Slabside, Oliver tried to warn Felton about Diaz only for Felton to not listen to him and to refuse to let Oliver help him find Diaz out of arrogance. When Oliver broke out of his cell to find Diaz, Felton warned him to stand down only for Oliver to refuse. Felton then pulled out his baton to fight Oliver only for Oliver to take him and the other guards out. Angered by Oliver hitting him in the stomach and for disobeying him, Felton told Oliver to kiss his early release goodbye. Felton's arrogance cost him dearly when Diaz orchestrated the prison riot and got the inmates to gather the guards. Felton and Miller were almost killed by the inmates until Oliver and Turner rescued them. After thanking Oliver for saving him and Miller, Felton told him and Turner that some of the guards made it to the panic room and some were taken to the mess hall by Diaz.
After Turner saved all of the guards, he returned to his cell, finding "The Count of Monte Cristo" book left for him by Oliver to read as he did, and acquire hope. Felton approached Turner, whom he helped save from certain death before, and Felton thanked him for saving everyone's lives, leading Turner to contemplate his redemption. Felton's kindness towards Turner made him become a better man than before.
Felton is extremely overconfident, to the point that he believes that Slabside Maximum Security Prison is impenetrable, as he believes that it is impossible for any individual to infiltrate the prison without anyone knowing about it, even when Oliver Queen try to warn him that Ricardo Diaz had escaped from custody, it was only after Diaz began a prison riot that he found out the hard way that Oliver was right. He is also at his core a law-abiding man who keeps the other guards in line, like B. Dunbar.
Unlike Felton's predecessor, Peter Yorke; he never badly treats the inmates and tries to get on their nerves for his own personal amusement, as he follows the rules just like everyone else, as he knows full well that even criminals have their rights, Felton also knows full well that being a guard does not mean that the laws don't apply to him, also unlike Yorke, Felton is loyal to the other guards; for example, when he learned that his friend Dunbar was killed, he (correctly) deduced that Stanley Dover did it and was ruthless enough to arrest him in front of Oliver as well as call him a "little bastard". According Stanley, unlike Yorke who was a hardass, jerk and dick due to his own personal issues; Felton is a professional jerk.
Felton is not above displaying respect for inmates who earn it such as when Oliver and Ben Turner saved him as well as Miller from certain death, also unlike Yorke, Felton displayed humanity for Oliver and Ben by thanking them for saving the surviving guards who were not killed in the riot, Felton even warned them about how a few of colleagues already died in the riot and that Diaz was killing them for sport, Felton was not sure what to think of Ben but after Ben helped save everyone's lives, he thanked him for it. Felton has respect for Oliver and Ben.