When I saw dxd in the title I gave up but when I saw no harem then I was instantly instilled with hope. No matter the Grammer or plot holes or any other bad things that might be in this novel (ps. I haven't read it yet) I will still read it because this is the first dxd fanfic that I've seen that doesn't have the harem tag. I will read this happily.
So.... The shock and awe is too much. The titles are an unnecessary distraction. Instead of going with such an approach, it would've been better you just played out the scene solely on the MCs POV. In that way we can make our own judgement on how ridiculously OP he is with out you telling us in such a roundabout way. Since after all, this approach makes it too crackish.