Klee's Dad: "Kleiner"
RIP to my "varka is klee's dad" crack theory and enthusiastic greetings to our fourth incarnation of "yssring leavtruth"!
Yssring Leavtruth AKA "Klein"
klein first appeared as a playable character in houkai gakuen (right & top left) and has additionally cameo'd in honkai impact 3rd (bottom left) and honkai star rail (centre left: boots from the "scholar lost in erudition" set).
in houkai gakuen, yssring was a kid genius personally recruited by welt yang to head anti-entropy's science division. she had a tragic relationship with the eventual herrscher of metal and was the creator of the playable character "femirins", an AI capable of human emotions. as an adult, yssring became a dean and teacher at honkai academy.
in honkai impact 3rd, "klein" is an ELF (Equipment: Living Form) working for the flamechaser mobius. it is later revealed that the ELF klein was modeled after a human klein who was tragically subsumed into the herrscher of legion. she is named for the mathematician felix klein who invented a kind of 3D mobius strip known as a "klein bottle".
in honkai star rail, klein was a historic scientist of metallurgy and #9 of the genius society. he was caught up in a tragic love triangle that was violently "resolved" by polka kakamond's killing at least one (if not all) of the parties involved.
"Kleiner"
i could well be jumping the gun in assuming that genshin's "kleiner" will be an incarnation of yssring/klein but, well, alice is just as mad as any one of klein's alternate universe scientific colleagues! i dearly hope that kleiner will be playable, along with alice, if only to allow silly shenanigans in co-op.
one thing i'm curious about is what, exactly, the name "yssring leavtruth" is a corruption of because the only thing that comes to my mind is "yggdrasil", the world tree in norse mythology, and that could have some very interesting implications for genshin's lore as a whole.