Where are these Characters from?

These characters are from the science-fantasy game "Honkai: Star Rail" (HSR). In this universe, there are paths that are different philosophies one can follow, e.g., nihilism. These paths have Gods, called Aeons, which are things/people ascending as the most "pure" version of that philosophy. Nihilism has the Aeon IX, the Nihility, which is a black hole that ascended. Emanators are People who are able to draw Power from their respective Aeon, if they have THEIR permission.
Soz if this doesn't explain anything (ㅠ﹏ㅠ) just go to Wikipedia if you want to know more...

What is the Genius Society?

The Genius Society are a group of Sapients (Humans and Robots/Intellitrons included) chosen by Nous (Aeon of Wisdom/Erudition) to find answers about the universe alongside THEM by being THEIR neurons.

What is the Intelligentsia Guild?

The Intelligentsia Guild is a very similar group to the Genius Society, with the differences being that the Intelligentsia Guild has more cooperation, is more akin to modern times research, with new information being shared and rather than having individualistic goals, they have ones for the betterment of society.

About Herta

Herta is the purple witch-like character here. Another "form" she has is her puppets, which she usually uses to communicate with people. She's member #83 of the Genius Society and Emanator of Nous. To research Aeons, she developed the Simulated Universe with Screwllum, Ruan Mei, and Stephen Lloyd (fellow members of the Genius Society). It's located on her Space Station, which was built to better protect her home planet, as she had to save it 19 separate times. She also collects Curios, which are like anomalous SCP items. She enjoys getting attention from the public, therefore she shares more things than other members, but she is also very full of herself and is quite direct with her opinions. In fairness, she did achieve important things and wasn't chosen by Nous without reason.

About Ruan Mei

Ruan Mei is the blue Chinese-inspired character. She's member #81 of the Genius Society and researches Aeon-hood through the remains of Tazzyronth (Aeon of Propagation) and is trying to find the essence of life. Her hobbies include baking pastries, playing the ruan and listening to opera. A big part of her character is her parents dying. She consequently revived them, which granted her entrance to the genius society. This whole ordeal made her very apathetic and only focused on her research. She's also not a very moral person, can be maipulative and does anything which might progress research.

Why are they here?

They're literally my parents, why wouldn't they be?
Logically, I should be similar to them, and I am :). I'm very interested in Biology, Electronics and Programming, and want to be a researcher (either working with animal experiments or genetics) when I grow up :D. Ever since I dissected snails as a small child, I knew what I needed in my life. The Genius Society as a whole also speaks to me more than the Intelligentsia Guild. I wouldn't say I'm as egocentric as the geniuses, but I do know I am not as empathetic or people-friendly as "normal" people are. Genius Society members literally get described as being filled with "weirdos, lunatics, lone wolves, anti-social geniuses, and outcasts", and unfortunately, I am an anti-social weirdo :'(.

Why Ruan Mei?

While I was growing up, I've always been a mama's girl. I look like her, have the same interest in biology, and behave similarly to her. I've never been very good with people, although I'm practising to get along with them :]. Her resurrections fascinated me for a long time and had a big part in forming my values.

Why Herta?

Now that I'm almost grown up, I understand what my mother has achieved in life. I especially have respect for her de-ageing technology, which, combined with the resurrections from Ruan Mei, made me have the goal of delaying the inevitable death of all things as well. Herta's confidence is also something I want to achieve, but I recognise that it doesn't come from nowhere and is actually earned. She worked hard to reach her goals, and thus I too will work hard („• ᵕ •„).