There must be something wrong with their R/L and S/Sh. I always get confused especially because of the translation (◉⌓◉)
Pretty sure this comic is Korean but in Japanese, L/R is blurred together into one sound and though sha/i/o/u exists, si does not. Korean and Japanese have a similar grammatical structure and being in proximity, it wouldn't surprise me they would have similar vocalizations.
Translators do have to take liberties when translating foreign names of characters because they don't know the author's intent until it is spelled out in Roman letters either in side note information or promotional material. This is easier to notice when a different translation group takes over and uses what they deem is the correct spelling.
My full first name translates rather well but my nickname, despite being a typical spelling, looks completely different in order to get as close to the pronunciation as possible. If someone didn't know looking at it and translating it back, they could easily come up with a totally different name.
The names suck... CLOWN? Why can't it go back to Crown, that makes so much more sense for a powerful and fearsome family. Also, I've given up reading her name as SHERina. Just call her Serena, the other one sounds like a speech impediment.