HU hand vs. Dreamclown

[ggbman]

Literally first hand. He opens in the SB, i 3 bet A3o, he calls. Flop is 663. I bet, he raises, i call. Turn is another 6 and i check call. River was some dud like and 8 and i bet/call. We like?

I was going to lead or c/r most turns, but when the 3rd 6 came i wanted to keep hands like 45 and 57 around to potentiall bluff at some point. Also, given his action, is betting the river here sound? I am obviously never folding to a raise.