Ren, or R39 as he was originally known, was not born in the traditional sense. Instead, he came into being in a secret underground laboratory on a small, seemingly deserted, island in the Land of Waves. The purpose of the laboratory was to create living weapons, imbued with multiple Kekkei Genkai, using the Chimera Technique, that would be then sold to the different Shinobi Villages.
Being the 39th Research Specimen to survive the process long enough to make it into the testing phase, he was given the simple designation R39. He spent the entirety of his life undergoing various tests, designed to improve his abilities and test the limits of what his artificially created body could do. He was subjected to lengthy periods of time deprived of food, with minimal water; locked into Sensory Deprivation chambers; and pushed to nearly every physical and mental limit imaginable.
It was, however, the only life he knew, and so it was one he lived, day in and day out, for years. It was, perhaps, the overreaching ambition of his creators that led to his freedom and their ultimate demise. The inherent blood rage caused by the Senninka trait had not been filtered out in the creation process, and the natural energy eventually built up to a critical limit inside him, despite being him spending much of his time sealed away.
R39 had no memory of the ensuing slaughter that resulted in the death of every other living being in the research facility, and awoke outside, lying on his back in the sun. Confused, but ultimately happy with his new surroundings, the young looking boy set off to explore this new world.
After several months of wandering, from island to island, finally reaching the mainland, R39 encountered a woman, Hikari, who caught him stealing water she had left out for her kitsune. Taking pity on the boy, she offered him a place to stay, as well as food and clothing. She even gave him a formal name: Ren, and used her knowledge of Fūinjutsu to place a seal on him that would aid with the prevention of further blood rages.
Due to the unique situation surrounding his creation, Ren is not a typical human specimen. Though a male, anatomically, he bears very few masculine features, and zero secondary sex characteristics, leading many who meet him to think him female.This misconception is only aided by his naturally pink hair, worn exceptionally long, and the effeminate curves of his figure, and even more so by his interest in feminine clothing and accessories. He is a fairly short individual, and rather light as well, leading to the impression that he should be weak and frail as well.
Though his clothing choices tend to vary from day to day, he has taken to frequently wearing the robes of a Miko, after having met and subsequently taking a liking to the former shrine maiden, Hikari.
Ren is often a sporadic and outgoing individual, who acts without thinking about potential consequences. He is a carefree person, who likes the freedom to go and do what he wants, when he wants.
Due to his past, though, Ren thinks little of following orders or direction, and will usually do what he's told without question.There are many times when Ren will come off as mischievous, or devious, and has a penchant for playing tricks and pranks on people, usually centered around his deceptive appearance. Additionally, on occasion, he can be downright manipulative and almost cruel, seemingly taking enjoyment in the suffering of others.
More than anything though, Ren will become attached to those who show him kindness, and do whatever he can to ensure their happiness, even at the cost of his own comfort and well-being. This can lead to him being easily manipulated by those he cares for.
Created through the Chimera Technique, Ren was given four Kekkei Genkai, each of them specifically chosen to compliment the others. In addition to these bloodline traits, he was created with the knowledge of a number of Shinobi techniques, both Ninjutsu and Genjutsu. Though his body might seem slight and small, he is also proficient at Taijutsu techniques, making him a dangerous opponent at nearly any range.
RinneganBecause his dōjutsu is not a naturally occurring ability, Ren must focus for a second to active the Rinnegan, causing his eyes to change from their normal pink to the trademark purple rings. While active, though, he has access to all of the Rinnegan's abilities. His most commonly used one is the manifestation of Black Rods, though rather than their typical use, he creates them as a Black Powder, infused with his Jiton charka, allowing him to control it like Iron Sand.
The second of his Chimera abilities, Ren has the power to change and shape his body at will, using it to create defenses and weapons on the fly. While this carriers with it the natural flaw of Senninka, Ren was given a seal to absorb the excess of Natural Energy, allowing him to avoid the inherent madness for an extended duration.
Ren primarily uses his Jiton to manipulate the Black Powder created from his Rinnegan, using it like Iron Sand to create constructs, weapons and shields. He is also fond of creating wings of Black Powder, using his magnetic controls to fly.
In addition to his other three Kekkei Genkai, Ren was created with the ability to access Koton techniques as well. This primarily allows him to harden parts of his body, strengthening the power of his Senninka transformations, and drawing attacks to the impervious areas with his Jiton.