First of all welcome to MTF
It's true, there are already a lot of threads about this topic and if you want to leave a comment you can search for them via the search function
Whats more is that Rodge has won 13 grand slams and Rafa only 5.
You can't compare this as Roger is a few years older
It's impressive what kind of career Rafa had for his age so far. Nobody knows how much more GS titles he is going to win, but who would have thought some years back he would ever win Wimbledon for example? Nadal had great results on all surfaces, even though he hasn't won a GS title on a fast court (yet).
I think the title of your thread is a bit misleading. Nobody owns the other
Nadal is a bad match-up for Roger, especially on clay, but even on that surface they had a few close matches which Roger could have won (like the Rome final 2006). On the other hand Rafa could have already beaten Roger in Wimbledon last year.
It's surely an advantage for Rafa considering the h2h that they meet so often in a claycourt final, but he has shown in matches on other surfaces as well that he is a player who causes Roger trouble.