The Huimanians are a species of human-like aliens created by TheGoldnGuy
During the very, very early years of human civilization, several hundred human cells, as well as some adrift kaiju cells, were sent into space by an unknown entity. After drifting in the black void of outer space for several hundred centuries, some of the cells began to form human-like creatures. The kaiju cells combined with the human cells and were distributed to two organisms, and said organisms gained their power.
Finally, after drifting in space for such a long time, these organisms, as well as some newly developed "human-only-celled" organisms, landed on one of Saturn's fertile asteroids and started a new civilization. This civilization dubbed themselves "The Huimanians", and started to evolve at the same rate of the human race back on Earth.
Fast-forward to centuries later, and the Huiman race is confronted with a new threat: Kaiju. Several alien kaiju attack their asteroid home, but the Huiman's who had been created with kaiju cells used newfound shapeshifting powers to fight back. These "shapeshifters" are thanked, and their decedents were given the status of king and queen.
Fast-forward to the next hundred or so centuries, and Huiman society is experiencing peace. They've mastered the art of science, and are somehow more advanced than their human brethren. The king and queens of the past years had done such a good job keeping the kaiju from attacking that the Huiman population had long since forgotten that there even was a threat, and nobody except the royal family actually documented the attacks. Leading to a major problem where if the Huiman population ever found out that there are almost daily kaiju attacks, then they wouldn't know how to handle it, and chaos would ensue.
Another century passes, and for the first time in Huimanian history, only one child is born as the heir(ess) to the throne. The child is dubbed "Humania". Shortly after her birth, her parents die from a kaiju attack, and Humania is forced into the role of Queen despite her age.
Twenty years pass, and Queen Humania has managed to maintain order by fighting off kaiju and attending her royal duties. But she begins to notice that the kaiju attacks are becoming more frequent with each passing day. Fearing the inevitable, she escorts a majority of the Huiman population onto a ship, no one questioning her rule. They set off for Earth, Queen Humania hoping that Earth contains friendly life.
Huimans are very similar in appearance to regular humans, but have adapted to the cold vacuum of space. Royal Huimans, having been created with the cells of kaiju, can shapeshift into whatever kaiju cell they inheritated. Royal Huimans also tend to have more slender physics than normal Huimans.