Nosaka Yuuma has spiky, reddish-pink hair and dreary, lightless gray eyes. He is tall and has a pale skin tone. His casual clothes consists of a black short-sleeved t-shirt, dark blue pants and white shoes. He is also seen wearing a pendant around his neck and a black bracelet on his right wrist.
He first appears during episode 1, watching the match between Inakuni Raimon and Seishou Gakuen alongside Nishikage Seiya. After Kozoumaru scores Raimon's first and only goal, he comments that their eyes makes it look like they are having fun while playing soccer. Nishikage replies that's impossible, to which he agrees.
In episode 2, after Raimon loses by 1-10, Nishikage comments the result was as expected. Nosaka agrees, but asks him if he could investigate Inakuni Raimon a little for him.
At the start of the match between Inakuni Raimon and Minodouzan, he was seen in the stands with Nishikage, and they ran into Haizaki there. After a small conversation about their interests in Inakuni Raimon, they went their own way.
He was later seen watching the match between Seishou Gakuen and Kidokawa Seishuu, commenting over the match and the actions of Haizaki and Kidou. After the match, he visited Miyano Akane and presented her with flowers, which she accepted.
In addition to all of this, He seems to display more emotions compared to the other subjects of Ares no Tenbin. this is shown in Episode 008 (Ares) when he gave Nishikage way too much ice cream.
- According to the trailer, he is known as the Emperor of Tactics.
- Nosaka's birthday is on April 2.
- It is known that he has some kind of illness due to the fact he collapsed and left a pill container behind in episode 13.