Another enjoyable overpair experience

[soah]

Hand was a few days ago so details are sketchy. 2/4 at Bodog. MP player limps, I raise right behind him to $18 with KK, unknown right behind me calls, all others fold. Flop J66 rainbow. I bet $30 and he calls. Turn is a 6. Pot is now around $100 and he has $300 left. I know nothing about him, but if he were a complete idiot or maniac I probably would have taken notice of it by now. What's my plan here? Am I looking to get my stack involved on this board, or am I folding if it reaches that point?

This is full ring so I am playing tight and have not done anything crazy during the time he's been around (I'm not sure how long that's been).