Through 25 hands, villain is
70% PF, PFR 18%, CC 7.4, TA: 2.5, FTF: 64%

Party Poker No-Limit Hold'em, $ BB (10 handed)

MP2 ($26.99)
Hero ($52.05)
CO ($20.37)
Button ($34.31)
SB ($48.50)
BB ($51.90)
UTG ($81.56)
UTG+1 ($98.37)
UTG+2 ($35.40)
MP1 ($52.60)

Preflop: Hero is MP3 with , . SB posts a blind of $0.25.
2 folds, UTG+2 calls $0.50, MP1 calls $0.50, 1 fold, Hero raises to $2.5, 4 folds, UTG+2 calls $2, MP1 folds.

Flop: ($6.25) , , (2 players)
UTG+2 checks, Hero bets $5.5, UTG+2 calls $5.50.

Turn: ($17.25) (2 players)
UTG+2 checks, Hero checks.
He called my PFR and check/called my flop bet. I gotta fear a set here (or an already made flush), so I check behind him hoping for a club.

River: ($17.25) (2 players)
UTG+2 checks, Hero checks.
Well this gives him many more outs, so I just check behind him.

Final Pot: $17.25

Comments on my play?

Amazing Party results to come soon.

A hand same opponent later played. He's the Button in this hand:
Party Poker No-Limit Hold'em, $ Hero (9 handed)

SB ($64.67)
Hero ($41.80)
UTG ($16.41)
UTG+1 ($49)
MP1 ($49.50)
MP2 ($49)
MP3 ($84.86)
CO ($69.81)
Button ($10.30)

Preflop: Hero is BB with , . SB posts a blind of $0.25.
UTG raises to $1, 5 folds, Button calls $1, 1 fold, Hero calls $0.50.

Flop: ($3.25) , , (3 players)
Hero checks, UTG checks, Button moves all-in, Hero folds, UTG calls $9.30.

Turn: ($12.55) (2 players)

River: ($12.55) (2 players)

Final Pot: $12.55

Results in white below:
UTG has 7h Ah (full house, aces full of fours).
Button has Js 9c (two pair, aces and fours).
Outcome: UTG wins $12.55.

I don't think you played it that bad. I think both checks are fine. I do think you could be beat by a set and he checked behind fearing the straight from you.

I can see the lack of interest in the 1st hand...

Anyway, he showed for 2 pair on the end to win. Can believe he called the PFR and then chased the OESD. Unlucky board for me that I checked it to him, but I suppose that's poker. Any bet on the Turn by me would have probably pushed him out.