Affection.

My boyfriend is not the touchy-feely, affectionate type at all. Which is fine and I accept it. But sometimes just a little extra affection would be nice. I've brought it up and he's great about fixing it after we talk but then it gets few and far between again, besides the nightly kisses and daily goodbye kisses I get every time. 
I know this is who he is and I don't want to change him for anything. But does anyone have advice, any words of wisdom?