Devomas are pseudo-mammalian space creatures with a humanoid body plan and face. Their biology is such that they have limited shapeshifting abilities. For those reasons, their appearance is not limited by their genetics and their looks tend to reflect their tastes. Likewise, their gender is not limited by the one that they had at birth and it can shift as they please.
They grow at the same pace as humans until they have reached adulthood, at which point their aging is drastically slower. A 20 year old Devoma looks like a 20 year old human, but a 300 year old Devoma looks like a 90 year old human.
They reproduce through a female/male binary - in the sense that there must be a "sperm donor" and a "carrier". That does not mean that either parents have to conform to human gender norms for that to happen as long as the baby carries the genes from both parents. (Self-fertilization/asexual reproduction, as well as cross-breeding with others species, is not canonically possible.) A Devoma, if they have the organs that allow for such a thing, will carry their child for 9 month in their abdomen, much like a pregnant woman does. During birth, the skin of the stomach splits, allowing the baby to come out that way.
Feeding
A Devoma feeds by siphoning energy from their environment, may it be electricity, heat, light, etc. They can naturally sense any energy source and will make their way to them before using their spinal ridge to absorb said energy. The way it looks from the outside varies on the source they feed from and their style. It can be through the mouth, the hands, or directly to the ridge, that then acts like a lightning rod, for example. The energy will then be stored in their tail, inside of "batteries", where it can be used later.
There are two type of "battery pockets" inside a Devoma's tail: long term and instant, instant representing the maximum of what a Devoma can use in a short period of time. A Devoma with a lean tail will live a perfectly healthy life, chubby being most prevalent among long-distance travelers that might only get a meal once in a while (or the descendants of such Devomas.)
Mutations
Devomas can alter their appearance and their internal organs, changing them over long periods of time. Those changes, when they are so significant that they change the structure of their body, are called Mutations. Mutations are often an expression of a Devoma's identity, especially when the Devoma chose it - they are, for the most part, already perfectly adapted for their preferred environments.
There is a wide range of mutations available to Devomas: their imagination is the limit. There are even cases where the mutations showcase the powers of the Devomas, such as with the trail mutations.
Scarring and Regeneration
Devomas can live a rough life and it not uncommon for them to carry scars. They can, in theory, regenerate any wound they receive given enough time, granted that it does not kill them, just like they can change their appearance as they please. One might think that this mean that there is no such think as a Devoma with a handicap such as a missing limb or eye, but that could not be further from the truth.
Because their mental state and identity is so intrinsically linked with their body, a particularly traumatic event might stunt their regenerative abilities. For example, if a Devoma lost their arm during a violent Wurthan attack, they might be unable to regrow it until they have worked through that trauma, like some physical manifestation of PTSD.
Going even further than that, some Devoma that went through purely psychological trauma (such as, for example, the loss of a close family member or a friend, an assault, childhood abuse, etc.) might see it manifested as mutations on their body. It doesn't always happen, but it is a reality for some Devomas.