While Albedo and Klee are not related by blood, Alice acted as a parental figure for Albedo and asked him to think of Klee as his sister. While Albedo's former master is the closest thing he has to a parent, Klee and Albedo have developed a bond similar to that of siblings.
Albedo and Klee aren't blood-related, but Alice helped to take care of Albedo and asked that he think of Klee as his sister. The two have taken on a sibling-like relationship, and Albedo is close to Klee.
6 Alice Is Klee's Mom
Her relationship with her daughter has been extensively explored in various in-game events. For instance, the Midsummer Island Adventure in Version 1.6 was specifically designed to offer a fun-filled summer holiday for Klee.
When Klee called Albedo, she called him Albedo-onii chan (big bro Albedo) or gege (brother), but the English version was Mr. Albedo instead. But then, when Albedo called Alice, he called her Alice-san.
There, the story unfolds that Albedo and Durin are "brothers".
Voicelines. In Kaeya's voiceline about Albedo, he flatters him by saying that everyone loves him, some more than others. He comments on Albedo's charm, saying "what, you into him as well?" implying that he is interested in Albedo.
Lupus Minor. Razor first mentiones Klee in his Story Quest. He and Klee have met each other before, as he mentiones her as Knight that is "Red and Hot" that helped him before and that "she" was here and set the whole forest on fire and the wild boars were all gone.
While Albedo and Klee are not related by blood, Alice acted as a parental figure for Albedo and asked him to think of Klee as his sister. While Albedo's former master is the closest thing he has to a parent, Klee and Albedo have developed a bond similar to that of siblings.
Klee loves her fellow knights, and is well-loved by them in turn. She is particularly fond of Kaeya and Albedo. Whenever she heads out of the city to play, she always follows the "survival rules" which Kaeya gave her. Albedo, on the other hand, is an older brother figure who takes care of her.
Klee's main focus is rapid and powerful Pyro blasts. Virtually every attack she performs involves some kind of explosive device, from her fast-firing Kaboom! bombs or her beloved Jumpy Dumpty cluster grenade.
It's possible that Klee's ears could be an aesthetic choice from miHoYo. But considering her mother could've come from another world, that could very well explain why Klee looks the way she does. On the flip side, the identity of Klee's father is unknown, so he could be equally responsible for Klee's ears.
When Klee was young, her mom spent tons of time encouraging her to pursue her passions. This included her strange fixation with making explosives even as a young child. Thanks to the fact that her mom pushed her to follow her dreams, Klee has now become a capable fighter.
A lot of people in the fandom has also thought that Jean was Klee's mother as well though it isn't as Klee's real mother is Alice, people tend to think that Jean just acts like a mother to Klee only.
"Primordial" Albedo (unofficial name) is a quest-exclusive NPC who appeared in the Version 2.3 event Shadows Amidst Snowstorms. He is distinguishable from the real Albedo by the lack of a golden star-shaped marking on his neck.
Albedo was born as a synthetic human being created by Rhinedottir, also known as Gold.
First off, during the cutscene with Alice's recording, we most notably hear about Alice and Klee being elves, with much longer lifespans than humans. We technically already knew that seeing Klee's ears.
Ainz Ooal Gown
As such, Albedo is completely infatuated with Ainz and is absolutely loyal to him. Even when he tells her that she only loves him because he made her that way, the only problem she has with it is if it causes him trouble.
Rosaria is extremely good at her job and can easily see through the facades the other characters like Kaeya put on. She is able to pick up that the Traveler isn't normal and is wary of the mysterious Albedo, who the game heavily hints at not being a normal human.
Klee's appearance in the hallway runs toward Traveler. She's ten years old with pale skin, orange eyes, blonde hair tied in pigtails, and elves' ears.
Klee's Elemental Skill, Jumpty Dumpty, lets her throw a bomb that can deal area-of-effect Pyro damage for each of the three times it bounces. After it lands, it splits into little mines that can explode once enemies make contact, or after a short duration of time.
Klee loves her fellow knights, and is well-loved by them in turn. She is particularly fond of Kaeya and Albedo. Whenever she heads out of the city to play, she always follows the "survival rules" which Kaeya gave her. Albedo, on the other hand, is an older brother figure who takes care of her.
7 He Considers Albedo To Be A Possible Threat To Mondstadt
As it turns out, Venti's concerns about Albedo are very much justified. In one of the cutscenes, the powerful Geo character expresses his worries about "losing control" and having someone to stop him if he turns to the dark side.
Among the numerous Floor Guardians and NPCs, Albedo is the only one who harbors hatred towards the creators, including the one who created her, Tabula Smaragdina. Despite acknowledging that she would not be alive without him, the hate she has toward him does not diminish in the slightest.
12 He Cares For Jean
Despite the fact that Diluc openly despises the Knights of Favionius, he seems to have a relationship with Jean. Some players even believe that the two may be romantically interested in each other. He is willing to team up with Jean to help with Stormterror and even helps to throw her a party.