Sapuns & Tispuns

Sapuns are a type of unbound with a strong connection to trees; tispuns are slightly more mundane variant. In most ways, a sapun or tispun is indistinguishable from a human, and although it is believed that sapuns once had their own great civilisation separate from humans, in the modern world, sapuns and tispuns are so integrated into human culture and society that most people consider their existence to be a myth. They do not appear to have their own language or naming customs, and in appearance can usually pass for a number of different human ethnicities. Although the current number of living sapuns and tispuns is unknown, their reality is well attested in older historical and literary sources, and reports of encounters with them are frequent enough to indicate a sizeable, if diffuse, global population.
There are three major aspects to the supernatural nature of sapuns. First, both sapuns and tispuns are able to communicate with each other and, according to some reports, with humans through skin-to-skin contact, and express basic emotions and messages non-verbally in this way. Second, they reproduce through magical rituals involving plants and trees, rather than through biological means: a pair of sapuns may bring forth an infant or adolescent sapun by conducting a regular ritual around a sizeable tree over the course of several years, while a single sapun may create a baby tispun in a similar way over a much shorter period of time and using a smaller tree or shrub. Neither sapuns nor tispuns are able to reproduce with humans, and it is believed that tispuns cannot reproduce through ritual means either, but rather are fully sterile.
Third, and most significantly, sapuns (but not tispuns) are almost immortal: although they age in the normal way, at perhaps only a slightly slower rate than humans, a sapun can return to the tree from which they were born and, through supernatural means, enter into its core and revert to a state of metamorphosis which, over the course of several months, rejuvenates the individual until they can exit the core of the tree with a younger and healthier body, but with their minds and memories intact. This process can even be used to rescue a sapun from what would otherwise be a fatal wound or incurable disease, provided that they are conscious enough to conduct the requisit ritual when they reach their tree; if there is another sapun who can complete this ritual on their behalf, a recently-dead individual can sometimes be returned to life in this way. It is thought that an individual might live for several hundred years in this way. If a sapun's tree is killed, there is no immediate effect on the sapun, but rejuvenation will no longer be possible, and this sudden curse of mortality can be traumatic and cause prolonged distress.