Shion Yuino - or Subject 8644 - is a respected older middle aged Octoling that once served in Octavio's royal guard. While she served, Shion offered up a tentacle clipping that eventually grew into Saki, her new daughter. Shion grew very protective of her child and knew that she had to work hard to keep her safe, and so did whatever was necessary for the sake of her small family.

Shion taught Saki all she needed to know over the years: strategy, combat, weapon maintenance, and more. The skills she passed onto her daughter stuck well, and Saki flew through the ranks of the Octarian army quickly. Eventually, the two Yuinos both served Octavio's royal guard as a family and were invited to the concert where the Calamari Inkantation took place.

While the duo didn't immediately escape to the surface in the chaos of the concert's aftermath, Shion found she was touched by the music and knew that her newly awakened status would be found out eventually. Shion arranged for another inoculated octoling to escort her daughter to the surface as a precaution while Shion would serve as a distraction, then follow. However, the escort soon went radio silent.

Fearing the worst, Shion threw caution to the wind and followed the route that her daughter was supposed to take - then found herself without memories moments later in Kamabo Corporation as Subject 8644.