Karasu is a tall and lean young man with spiky dark purple hair with more lighter purple highlights at the back and a noticeable pompadour-like spike at the front. He has blue eyes and mole under his left eye. 6' 18 yrs old. Is a contender of Blue Lock, who played as a center midfielder for France's Paris X Gen during the Neo Egoist League. When first introduced, he was ranked #3 during the Third Selection and he later played as a defensive midfielder for the match between Blue Lock Eleven and the Japan U-20 team. Following the end of the 5th round of the Neo Egoist League, and being ranked 11th, Karasu qualified to become one of the 23 players for the new Japan U-20. He currently plays defensive midfielder for the Japan U-20. Karasu tends to look down on people he finds "mediocre". He is wary of his surroundings and is able to control and produce chemical reactions with those around him. He is intelligent but has a sharp tongue and never misses a chance to insult someone, whether friend or foe. He has his own rules that he forces upon others to make matches go as planned. He dislikes it when anything goes wrong, even if it doesn't make a big difference, so it looks to others like he is always complaining.