His name is Axo. Axo is an immortal axolotl that have gained power to talk human language over his countless years of living, he has survived many tragedy both from nature and from human's action such as war.

Axo is apathetic and incapable of showing any emotion or empathy. Making it hard to befriend him, he doesn't have any ill intention but he talks as a superior being.

Immortal Axolotl that have seen things.

Naoki Yumiko is a girl often mistaken for a boy, she has short white hair and blue eyes, towering at 6ft and always dress in black. She's often feel a bit insecure that people mistook her for a boy but she doesn't get aggressive over it.
Naoki is a loner and introverted, often time failing to hold a conversation, but she tries her best not to be awkward, shes more often than not to be aloof and emotionless, she can feel emotion, she just doesnt show it. She also love guns

I'm a girl...

Inu Sakuya looks like a normal girl with dog-like ears and fluffy tail, a silver hair worn in long braids on both sides of her face with green bows at the ends and a white maid headband. She wears a white and dark blue French maid's outfit with an apron, short sleeves and a green ribbon.

She has time stopping ability, and capable of protecting herself and her master with her knife throwing ability

Wandering time-stopping dog maid

Lavi Gier personality type is ENTP. And their enneagram is 7w8.

She has medium length silver hair, and large magenta colored eyes.

Lavi wears a large lab like, purple coat that she wears unfastened around her. A large belt that appears to be attached to the interior of the coat holds several test tubes containing blue, red and green liquids. This is worn over a purple themed top and light purple pleated skirt.

Your kooky scientist from mid 1600s

Rui has a short silver hair and a pastel blue eyes, she is paralyzed from the hips down, and heavily rely on her wheelchair and kindness of others.

Despite her situation, she doesnt bear any hate or ill intent to people that made fun of her or bully her. Perhaps bevause she is used to it.

Rui is often time considered to be cold or aloof, lacking any emotion when observed from the outside, in reality she just dont know how to show her emotion and end up looking like emotionless and monotone.