The synopsis is a little weird. It's like you wrote the same synopsis in two different styles. Personally, I prefer the way the last paragraph is written. It's more 'down to earth'. I suppose a small rework to that first run-on sentence might help.
Now then. Onto the bones. As the above person mentioned, you'll want to add the
Girl's Love genre. Also consider carefully reading through SH's Tutorial.
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To do what I can do, other genres you might add are: Action, Isekai, Mystery, and Supernatural. Whether you add them or not will depend on how much fighting the Protag does, how quickly you reveal the plot's 'secrets', and if there are more creatures like the Nightmares lingering around, or if they're a onetime deal.
Oh, for the Isekai one... If you do add it, make sure you keep the mention of Elca and Lita in your synopsis so people know she's not coming from Earth.
You'll also want to max out and hit the 25 tag limit. For example, you could consider adding Tomboyish Female Lead and Coming of Age. You don't need to add them all at once, but look through all the
tags and try to hit the limit. The more tags you have, the better.
Overall, it's a good story, with maybe just a touch too much description for a webnovel. That's not a bad thing.
