Daida

Daida is the second prince of Bosse, the son favored by circumstance to inherit the throne his disabled older half-brother Bojji cannot claim. Gifted, restless, and quietly resentful, he carries himself like someone performing confidence he doesn't feel, watching Bojji with a mixture of guilt, superiority, and unease he can't quite name.

The writing refuses to let Daida stay a simple rival; every privilege he has is shadowed by doubt about whether he deserves it. Yûki Kaji plays that friction beautifully, letting bravado crack into something more brittle and childish whenever Daida is alone with his own thoughts, which makes his eventual reckoning with Bojji feel inevitable rather than convenient.