Will be posting a post soon, have to address something first.
@AristoclesThis is my bad for not picking up on this sooner - I seem to have misinterpreted something in your backstory - but a Dracon Kingdom is not something that could exist in this setting. When you mentioned a homeland, I thought you were referring to an area where your species originated, not a full-on nation.
The only way a non-human nation could exist is if it is hidden so completely that humans are utterly oblivious to it's existence, allowing those within to safely survive without threat of humans. However, if this were the case, then no letter would have been sent - it makes no sense to invite one specific member of a species that is already safe to come live in the safety of the manor.
I fully accept that it's my fault that I didn't pick up on this issue earlier, but this needs to be addressed.