Spice of Life
The Spellbinding Forest
The entire perimeter of the forest--as well as the road barriers that slice it right in half--are protected by barrier spells so that those branded with the sigil are physically incapable of stepping out of bounds, as if walking into a solid, electrified wall. While it is possible to remove the sigil, only those who can place it are able to also remove it, which leaves the curse more or less permanent for most.
There are safer areas of the forest but there's no true safety within, and therefore it is ill-advised to enter without the capability to protect oneself from tricksters and monsters that may want to rob, kill, or even eat you. Those with higher magic ability may be able to create safe zones and live peaceful lives. Not all residents of the forest are mindless beasts, and often you may find seemingly normal people behind the borders, and you can even befriend creatures within the forest.
A darker truth that many may not know is that any outside human unfortunate enough to wander into the town and attempt to leave in fear or with threat of exposure will be captured. If questioning them leads the police to think that they will threaten the safety of the town, they will be released into the Forest. Few survive the way out, and those who do are often too damaged to threaten the town's safety.
Town Size, Population, and Economy
The town is designed to cater to human-sized people, therefore those larger or smaller may have difficulty accessing facilities unless they're in a location that's specifically designed for their species to access.
This does not count the population in the forest, which is uncountable.
Magic
Due to different headcanons of how magic functions and the hundreds of schools of magic that exist across different platforms, cultures, and fantasies, the actual spells contained in the book and how they work are left completely vague and up to the writer on how they want to portray it.
Not everyone can perform magic, even if they're non-human, and this is normal. The academy offers normal acedemic courses alongside the magical courses, ensuring all citizens get a full and proper education suited to their needs.
Reproduction
With that said, it's not as easy to actually have a child. Hybrids can have complications, especially those with conflicting genetics. Some can merely be born sterile, some might be chronically ill, some can be perfectly healthy. Sometimes, the chances of actually reproducing outside of one's own species is exceptionally slim, but it is never impossible.
As the writers and those who have hybrid characters or wish to procure hybrid offspring in-character (Or, conversely, don't), you have the power to decide how effectively two species might be able to breed together, and you're in control of the results.
It's of further note, visibly hybrid characters may often face some sorts of discrimination, depending on their mix and the culture involved with their parts. Most creatures tend to pair with similar or the same species, which makes hybrids rare, and that's why it's that way. How this is portrayed is also completely up to you as the writer.
As a final note, characters that are naturally infertile are incapable of breeding, as would be normal, and will not have a chance to produce offspring in Arcadia's setting.