I shit you not, this might be the best fanfic I've read on Webnovel, and easily, EASILY is one of the best fanfics I've read in general.
The writing quality is a solid 9/10. I could see it being a bit better, with some spelling/word placement mistakes and a few run-on sentences, but to say it's anything less than proficient grammar would be disingenuous.
World Building is a 9~10/10, with the score being interchangeable. You've managed to make a completely different yet respectable world from practically scrap loitered on a sh*t-stack called Jujutsu Kaisen(not jjk hate, just not enough world building for the heian era). My only personal gripe is the DXD crossover, at least an aspect of it. I just do not enjoy the whole 'gods' thing, and even now, I have trouble understanding exactly what the hell happened with sugawara and his ascension. Though, for the score, my personal opinion had been put aside.
Character Design is, again, a solid 9/10. The descriptions you ever so seemingly amalgamate create an almost picture-esque image in my mind, and the way you let it flow naturally with the story itself is telling how much effort you've put in writing. I have no complaints here; I don't think I have the skills to even complain at all in this regard.
Update Stability is probably a 10/10? At least, I'm hoping it's a 10. I don't mind waiting a month to read a chapter, given how most chapter-by-chapter novels wait that long, but I would prefer it to be sooner. Even then, a 10/10 as long as it's anywhere below a month or so.
Since apparently I've kinda f*cked up the order of the list already...
Story development is without a doubt, no questions asked, 10/10! Not once have I read a fanfic with such an immaculate story development. The way you could just weave a story as if you are Clotho herself is mind-boggling to me. such fluid, 𝘧𝘳𝘪𝘤𝘵𝘪𝘰𝘯𝘭𝘦𝘴𝘴 storytelling is not what I would expect from actual 𝘣𝘰𝘰𝘬𝘴, let alone a FANFIC!
Overall, a hard-earned, ABSOLUTELY well-deserved, 9.8/10!!!