For added context, during the first Hololive EN colalb with all five girls, they pulled up a diagram and tried to place each person on that diagram. Top was pure. Bottom was lewd. Right was smart. and Left was dumb. Kiara got immediately put into bottom left since she was already hitting on Callie. Her character designer, Huke (who also did character designs for Black Rock Shooter and Steins;Gate) latched onto it as well. In the coming months, Kiara has just continued to make lewd comments or do dumb stuff, like talking about her thigh fetish, pronouncing thighs as "ties", take screenshots of cute girls in swimsuits in video games, find diamonds in minecraft and immediately fall into lava and die, turn into a frog, and get banned from youtube briefly so she had to redebut and acted like she lost her memory.
Callie isn't actually that bottom left, but often unintentionally says stuff that are really easily taken out of context. She also did a "date" stream with the chat where she got attacked by a bird, hit on by ghost rider, and then did a pocky challenge but it was actually a stick with mud on it.