I love both of you but, seriously, who's the seme and who's the uke?

OOC: Personally, I don’t like the stereotypical seme/uke contrast in ANY pairing, in particular between Zoro and Sanji.
According to my own vision of canon there is a “top” and a “bottom” which is not pre-determined and constantly changes, depending on situations, moods, cravings and so on.
In short: ABSOLUTELY REVERSE.
Who tops more?
Useless to ask them. Zoro and Sanji will never talk openly of this touchy subject. That’s the way they are. So let’s take a peeky-poo in one of their *very private* conversations…