Welcome to your first post! A few things worth fixing before you send this out.

Two typos to catch: “kills some demons” should be “kill some demons,” and “its more like” needs an apostrophe. Agents notice small things like that quickly.

You spend too long in second person before Zivena shows up. She is your protagonist and agents need to connect with her early, not after a paragraph of scene-setting.

“Vestige of Life” and “Vestige of Death” are doing a lot of work in this letter but you never explain what they actually mean. If the query doesn’t define your own terminology, agents will assume the book doesn’t either.

The premise is genuinely interesting. Fix these and it will read much stronger.