Thanks for the reply. Just in case anyone else sees this and wants to express an opinion, I'll post the spoiler and discussion thereof in white.
<font color="white"> *** SHOW DOWN ***
Villain - Show cards [Kd,Kh]
Hero - Lost mucks
*** RESULT ***
Total Pot($8.50) Rake ($0.40)
Board [Kc,10d,5c,6h,2h]
Villain - Total ($8.10) HI
$8.10)Three of a kind, kings [Kd,Kh -
P:Kh,P:Kd,B:Kc,B:10d,B:6h]
GTANK86 - Folded on the FLOP
Hero - HI: [Lost mucks]
So I entirely got taken by the limping with a premium hand and slowplay of top set. He played it well and I got stuck paying him off. As I said for some reason at the time I was playing I thought his two pair made on the turn would beat mine, which was obviously just wrong (possibly attributable to my inexperience 2-tabling); perhaps I even should have played it slightly more aggressively, but I don't think so.
At any rate, probably just an unlucky hand and a tricky opponent, but I just posted it to check others' opinions. </font>