What was Valkyrie referring to when Seiya stopped her from saying it in episode 9 of Shinchou Yuusha? I just watched Shinchou Yuusha episode 9 and there was a point where Valkyrie was referring to something like "you will worn out..." and then "I see so you've already caught on".

What was she referring to? The manga is a lot behind the anime, and I can't get a physical copy of the light novel in where I live, and can't find this answered in any discussion threads.

I don't mind the spoilers at all, since someone who searches this exact thing is looking for spoilers in the first place.
Perhaps Valkyrie is not a god (maybe demi) and therefore Seiya should be able to use her techniques. I came to this conclusion because I did not see any of the other gods bleed before. I could be wrong though since I did not bother to double check the previous episodes.