https://www.mangago.me/read-manga/lv_99_princess_of_black_flame/uu/br_chapter-275434/pg-1/Keep scrolling and you will see Si-U.Same name, different family name.Same black hair and blue eyes, and slightly curt cool way of speaking.
And his species changed from cat to human that is incarnation of dog deity.
https://www.mangago.me/read-manga/lv_99_princess_of_black_flame/uu/br_chapter-275434/pg-1/
Keep scrolling and you will see Si-U.
Same name, different family name.
Same black hair and blue eyes, and slightly curt cool way of speaking.