Sometimes derogatorily called the "Feralkin", these humanoids are primarily known for their very particular relationship with the dead and spirits, and therefore their name.
While there isn't a specific real-world comparison for their appearance, they can be described as somewhat cat-like. The most iconic element of their appearance, though, is their masks, unique to each Spiritbound individual and a representative of their relationship to their bond.
All Spiritbound individuals wear a mask, but children only wear a simple, wooden mask, since they have yet to earn their Spirit mask, which comes when they come of age.
It always takes some time, finding and bonding with the right Spirit for a specific person, but when it happens and the connection is strong enough, the Spirit will give to the individual a mask to represent their connection. Once the mask is given and the commitment to each other made, separations between Spirit and person rarely happen and not without good reason.
Since masks are seen as so important to the Spiritbound, to see one of them unmasked out of their own free will is one of the highest shows of trust and affection in their own culture.
When it comes to religion, the Spiritbound first and foremost venerate their ancestors, and tied to that is this culture's closest thing to a patron deity, the paired spirits of the Mother of the Wilds and the Huntmaster.
The Mother and the Huntmaster, in the belief of the Spiritbound, are the first paired and bonded team of person and Spirit, and where the rest of the Spiritbound came from as they are now.
The island that the Spiritbound made their home in is quite a unique place, a giant yet dimly lit forest, overgrown with glowing lichens and mushrooms. This group makes their home in the branches, carving into the trees themselves to make their homes.
When it comes to how these houses are organized, the kitchen and living room are on the uppermost floor, where the entry is. The bedrooms and other rooms tend to be carved in a downwards direction, rather than upwards, to avoid smoke and steam getting into the bedrooms.