https://fastnovel.net/shield-hero-with-barrier-magic-9683/
Its is one of the best fan fictions I have ever read. Thank you for this!
Here is the site for those that are unable to find it.
Shame fastnovel is full of viruses, and I was straight up not allowed to go to it for it being phishing, sad, I really did like the novels, this one and the dxd one.