Before reading the story, I genuinely couldn't tell if this is an FGO parody or not. The premise deviates so heavily from the game's that I wouldn't have though that they could be related, were it not for the the backdrops and Mash's sprite.
Artistic license is taken to 11 here. There's mentions of characters and objects and crap that I don't know whether she straight up made up or is pulling from other titles in the franchise. It's all very confusing and needlessly detailed for something that doesn't show up later in the story whatsoever. It wouldn't be so bad, had it not started off with an info dump of things that makes me wonder "How the hell is any of this supposed to be Grand Order?" and follow it with more seemingly random exposition.
The writing itself is rather juvenile and dry. It's full of fluff and reads like someone's wish fulfillment rather than entertainment. I had to keep reminding myself that the character is supposed to be 27 or something, and not a teenager. The descriptions in the sex scenes are often cliche, overly simplistic, yet overly wordy. Here's a couple excerpts.
- "He bites my nipple just enough to cause a jolt of pleasure to shoot through my body."
- "Taking my ass in his hands, he pulls my hips down so the lips of my sex meet his tongue."
Despite advertising itself as a FGO parody, very little has to do with it.
- FGO's summoning system, which literally allows for a harem, is swapped out for "SERYPH" (presumably from Fate/Extra, which I've never played), for no apparent reason than to add angst.
- Gudako/Fujimaru, your generic placeholder for the player, is swapped out for some OC. She apparently "have dragon born" (trust me, it doesn't make any more sense in-context) and is apparently the most powerful mage because of alchemy or something. People shower her in praises, not for saving the world, but for being powerful/talented. There's like some kind of OP sounding made-up magic thrown in there that only serves to polish the OC further.
- The mysterious servants that our protag "lost" and "didn't ask for" are Cu and Emiya. They're wildly out of character and if they weren't named, I wouldn't know who they were.
- At no point does "[defending] the very flow of time itself " feel like it's important to the story.
To summarize my experience, I felt like very little attention was paid to the story and the smut, and too much of it was spent on the protagonist's superficial qualities. I hear more about her than the love interests combined! This isn't an RPG, this doesn't even have its own images. The reader's whole experience relies on good, immersive writing. What I got instead was some some annoying character drumming up random backstory, confusing inconsequential additions, and smut so vague and basic that I'm wondering why it was included at all.
tl;dr It reads like your typical Fanfiction/Wattpad/AO3 smut, starring Cu and Emiya.