Any head canons if Ren and Anna fought a battle?
Hello! Thanks for the ask!
Ren vs Anna, uh? That's an interesting question! Well…
On one hand, Ren is a more experienced fighter and Anna isn't as buff as most other characters, so if she takes a hit it'll hurt her like a bitch.
On the other side, Anna has several times his furyoku and has the exact knowledge of his personality to get him going and waste his energy.
Plus, on Anna's favor we have that she's not a direct fighter. She has two shikigami, so she has the possibility to defend and attack at the same time, not that I think she would, she's not the kind to play it that close.
And then we remember that Anna can nullify furyoku.
So all in all she's going to kick Ren's ass til he reaches Pluto.
The only way I see her having trouble is if he fights with Spirit of Thunder, which is naturally stronger than Anna's shikigami, but even then, the furyoku difference would make itself present. RIP Ren's pride.
In any case, Ren would fight to win. He may not start like that, he's not seen her fight first hand as far as I remember, so excuse him the scepticism. Still, his ego would not enjoy having his ass handed to him, so he ends up fighting with everything, no holds barred. Still not good enough.
As to how they end up fighting in the first place… Training? Anna told him to do something and he refused, so she told him he could avoid it if he won against her? (That's evil, Anna, you know you'll floor him.)
I'm torn between everyone wondering why Yoh is so relaxed about the fight (he knows she'll win) and them missunderstanding his attempts to stop it (he knows Ren's ego will suffer).
And that's all I can think of! This was fun, thanks again for the ask! :)