Older brother is my favorite character. He's so hilarious. He does stereotypical things for a character of his design, but he does that almost ironically but unironically at the same time. lol
I liked him ever since his first appearance and he's only gotten funnier since.
The two older siblings have been my favorite part of this series for sure. This is kind of one of those cases where the main characters are good, but the side characters are way better.
If the two older siblings were to get together in the future, I'd love it if the author made a spin-off focusing on them.