That's why its fiction hun
You do realize it also happen in real life right ? Also i am just saying its weird reading it since its very different from my reality and environment around me so it difficult to emphasize with the character
It's probably different for everyone. Me for example, had a crush on my cousin (take note, that was like when I was 5 or smthh, now I just wanna whack him lmao). But it's different for everyone. Some still continue to have feelings. Feelings that may have stemmed from difference situations and reasons, like admiration or that person played a huge role in their life at some point or smthh.
Note, I'm not saying incest (even with half or step siblings) is right or wrong. Just wanted to explain my theory on why things like this happen
The premise of liking your own siblings is so weird for me even when they are step siblings because i have both biological and step siblings but i still wanna punch all of them at least once ╮(￣▽￣)╭