Kohriinaur

I got him because he reminds me of Niche, even though they are different colors and personalities, lol.

Not an older brother~ Well, I guess he could be considered older, since Sai was literally reborn, but... If you go by their demon ages, the brother is younger by about 3 minutes. And he's an ice demon. -coughs- Which means he has an advantage on Sai, because melting the ice makes lots of dangerous water~

Kohriinaur Snowfauren, or Yuki Blackfoot as he prefers to be called, is Sairune's twin half-brother. (He has a different father from Sai, but they were born from the same mother at the same time).
Both boys take after their fathers when it comes to elements and personalities, but... Well, here's why he's Sai's brother: