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We all know the first line of a query is your "hook." I call the last line the "sinker." You want it to punch them in the face, in a nice, friendly kind of way that makes them unable to forget you after having read the 300 other queries in their inbox.
If you're looking for query advice, but are slightly intimidated by my claws, blade, or just my rolling googly-eyes, check out the query critique boards over at AgentQueryConnect. This is where I got my start, with advice from people smarter than me. Don't be afraid to ask for help with the most critical first step of your writing journey - the query. My comments appear in green.
Wolf, a teenage soldier of Māori descent, struggles with his asexual identity as he fights to protect the Empire from the Rebels. Their forces are growing stronger, fuelled by every wrongful death at the hands of the Emperor. They have to be stopped, before everything Wolf has ever known is destroyed. A few things - this sounds like high fantasy or sci-fi, but you have a descendant of a real-life tribe mentioned here. I'm not sure that's the best approach. Also, while the asexual identity is a good character trait to mention in the query, it has nothing to do with anything else going on in this hook.
Once a scamp on the streets, and now a star soldier in the Army, Wolf is still as alone as ever. Loyalty to the Empire is crucial, and so he must stand by as all troublemakers are executed, despite his growing misgivings about the Empire's methods. Questioning orders is not an option. This would almost make a better hook - your intro paragraph is rather generic. It could be the lead in to just about any "rise against the power" SF/F tale. Consider blending this with Rebel mentions in first para to create your hook, and leave LGBT mentions for title, word count para at the end.
After discovering a traitor amongst his fellow soldiers, kill the comma here and watching his friend die in a Rebel ambush, Wolf can't tell who to trust. One by one, lies, secrets, and betrayals are unveiled. He starts to suspect Pablo, a Training Instructor, of working with the Rebels, but when Wolf reports his suspicions, attention is drawn to him and his sympathy for the scamps. As even his own mind turns against him what does this mean?, Wolf struggles to cope with the responsibility the Emperor has given him.
The Emperor has a plan to defeat the Rebels. Wolf is forced to make a decision between listening to his conscience and losing everything he's worked for, or agreeing to set a trap for the Rebels, using his own people as bait. This could be their one chance to win the war. But Wolf is no longer sure about what he's fighting for. Again, I'm not seeing the asexuality coming into play at any point in the plot. Don't just use it in the hook as an attempt to draw in an agent unless it's truly important to the plot.
THE EMPIRE is a young adult dystopian novel of 85,000 words featuring a diverse LGBT+ cast. It's a stand-alone book with series potential. The mention here of LBGT is great - I would stick with this as your mention of character traits because it puts it out there without making it seem like a focus, which makes me think is a better representation of the book itself.