Roy, a 6-foot-4, 225-pound defensive end, selected Pitt over offers from Ball State, Boston College, Bowling Green, Illinois, Kent State, Miami (Ohio), Middle Tennessee, Ohio, Toledo and Western Kentucky.
Reading coach Scott Thamann told Cincinnati.com: "He liked so many schools, but Pitt really stood out for him. He really liked the campus and the coaching staff. He likes that they want him to play a true 4-3 defensive end."
Roy earned a first-team all-league selection last fall after registering 22 tackles for loss and 16.5 sacks.
O'Neill, a 6-foot-5, 235-pound tight end, also was offered by Coastal Carolina, Colgate, Old Dominion, Tulane, William & Mary and Youngstown State.
The Panthers held just one commitment -- from three-star guard Connor Hayes (Traverse City, Mich./West) -- entering June.