The villain seems reasonable, but he keeps on calling our raises, especially from the blinds. I'm not sure why, because we have only been raising pretty solid hands. He hit the flop pretty hard a few times, and generally checked flop and turn and 1/2 bet river if we checked the turn (so we have paid him off a few times).

I'm struggling to understand what his betting pattern means here. Is he putting us on tilt? Or does he more than likely have a monster?

Full Tilt Pot-Limit Omaha, $0.02 BB (5 handed) - Full-Tilt Converter Tool from FlopTurnRiver.com

SB ($1.82)
BB ($4.29)
Hero (UTG) ($2)
MP ($2.22)
Button ($5.88)

Preflop: Hero is UTG with 10, 10, A, Q
1 fold, Hero bets $0.07, 1 fold, Button raises to $0.23, 1 fold, Hero calls $0.16

Flop: ($0.48) Q, 5, 9 (2 players)
Button bets $0.48, Hero folds

Total pot: $0.48 | Rake: $0.03