The only kind of widely accepted invasive augmentation in human space grows within someone's body, essentially relinquishing the influence of its creators to become a new, independent organ that evolves with one's experience and life. This organ is called a monad. Monads are an ancient concept dating back to the late Low Age. Designed as artificial glands used to filter toxins, monads have evolved beyond their original purpose to serve as the universal companion of interstellar humans - and indeed, more than 75% of humans possess a monad.

In simple terms a monad is a small semi-artificial organ that is implanted at the base of the neck during the wearer's childhood, growing in complexity with time and reaching full functionality during the teenage years. Monads are capable of synthesizing a vast array of organic compounds which can then flow freely through the blood and lymphatic systems. In the historical concept of monads, these compounds were on-demand, custom antibodies used to counter toxins and poisons. Modern monads are still very good as toxin sentinels, but they can also cover a wider array of uses, synthesizing hormones, drugs and other compounds to affect one's body. In particular, monads have two mainstream uses: planetary adaptation and sex change. In the planetary adaptation process, monads are used to combat gravity-induced dizziness, trigger or reduce muscle growth, neuter allergy-inducing elements and more broadly speaking control a wide array of parameters to facilitate the wearer's life on a new planetary or station environment. In the sex change process, monads synthesize hormones to facilitate a transition, either at will or through medication-induced reactions.

Monads can be controlled via medication and specific self-therapies but one should always keep in mind that they have a life of their own. They aren't just augmentations, they're symbiotes that evolve throughout the life of their owner, sometimes unexpectedly. Repeated exposure to high-g trauma will lead a monad to synthesize anti-g drugs faster and more easily. Common exposure to toxins reinforces a monad's antibody manufacturing capacities. And so on and so forth: a monad will often reflect one's life and experiences.

Thus, immature monads are simplistic organs that are no more than organic factories. Mature monads, developed after childhood, start growing a small nerve system that is used for self-therapy interfacing. Old monads, appearing after the wearer is 30 to 40 years old, present a very complex nerve network referred to as a weave that organically stores sensory inputs and ambient thoughts, acting like a confused, complex library of memories and evocations reflective of one's life. The weave is also capable of interfacing with the nervous system, triggering a wide array of sensations or perceptions. This property sees great use in tech/human interfacing.

With the way most attempts at digitizing consciousness have ended in complete failure in the past, with current R and D on the topic being in a dead-end of nightmarish pseudo-AIs and artificial dreams, weaves are the best way someone's memories may outlive their own body. While using extracted monads to read someone's memories and past feelings is an extremely heavily controlled activity reserved for the family members of the deceased, some cultures have no qualms using them for different purposes. Among such groups is qith Sahaak on Elora, which has developed a complex method of turning weave memories into implanted reflexes and custom muscle memories, passed on from generation to generation.