Kitaag is a strange place, where many possible timelines are actually connected by the nexus-like Vermillion realm. As thus, certain people have many faces across the timelines, some much, much stranger than one would expect.
Take this for instance. In the "true" timeline, Yumi the Hebiri found a Vermillion-smithed soul-gem amulet. It bonded to her soul, laced into her chest, and drew her down the line that eventually would become Roboyumi, the Vermillionic ambassador of sorts. Troubleshooter, problem fixer, and more. But, what if Yumi found something else?
Meet this timeline. a mimic of sorts. This Yumi found a similar item in that car wreck in the plains; but instead of the amulet; which was chronologically isolated- a strange core was found; a metallic, glowing orb built around a chunk of weird flesh suspended in a fluid. It beats like a heart... Unbeknownst to her, its a piece of a Vermillion Reaver's flesh. And it needed a host.
The core, built by a corporation unique to this Yumi's timeline, Trifectum Enterprises, soon found its way onto a sleeping Yumi's chest, burrowing, agonizingly, into her flesh. In a sea of pain and fire, this Yumi was reborn as something new. Her heart burnt away, the core becoming her new heart, the malleable essence of the Reavers was engraved into her very soul.
For a day, her form laid as a melted pool, unable to hold itself together, until an eye appeared. Then a mouth. Another eye. An arm. Eventually, a changed Yumi staggered out, with much of her original possessions missing. They were granted a form of sentience by the power of the core, and they had left. But her scarf- an item she's had since her time as a hatchling- remained, changed as well. The power to awaken items...? How strange...

Over time, the wandering Yumi would find that she has control over her form. Focusing on it hides all of the irregularities, down to the Vermilionic static in her sclera, but when she's more casual, eyes, teeth, and the like tend to appear. She can also force her body to take the form of other things, from items to other biological beings, though when the changes are drastic, it hurts. Arm splitting to teeth in combat? Searing, but short lasting pain. Shifting from her Hebiri-like appearance to a wild, vicious beast? Agony. But again, short lived, as once the nerves connect, the pain subsides quickly.
Do it too much, and the heart overheats ! Ejecting itself from her chest, it dangles from wires of steel, energy, and flesh, exposed. More searing pain for the minute until it finally cools down. Its a good thing this Yumi has accepted the pain as just part of her existence.

Time passes, and she drifts away from herself to a degree, accepting the Vermillion energy that seeps into her soul, changing her- or perhaps it- entirely so, that it may not even be a yumi anymore. Disconnected from its old mortality, accepting that it is something entirely new. Perhaps, one day, it will have a meeting with Roboyumi; its Vermillionic opposite. But for now... watch out. You may end up as its toy to play with, for when it sees you as just mortal, all gloves come off...