Both of course!Your wife is cuckolding you with a big black guy. He cums in your wifes pussy and she tells you to either clean her pussy or clean his cock.
What would you rather do?
If you lick and suck the cock clean first, it lets you take your time to really concentrate on the creampied pussy.
Doesn't that just make sense?
Only way to know for sure is to try both and find out!