I heard that pineapple in his diet makes it taste better.
Any citrus juice will do this, but as you are aware it takes a few days to make a real difference in his/her flavor.
And with that, if it's what pleases him, I'm quite content to have him cum shallow or deep as per his desire and swallow his load whole. However, if he's a truly visual creature, he can cum in the warm wetness of my mouth, but I'll let it ooze out to coat his shaft once more so he can watch me as I lewdly lick it and eat it off his cock, belly and balls.