|Name (Kanji)||城山 翔斗|
|School||Yamaboshi High School|
|Club||Jazz Band Club|
|Seiyū||Ichiki, Mitsuhiro (市来 光弘)|
|Novel Debut||Volume 4, Chapter 2|
|Anime Debut||Episode 14|
Shiroyama Shouto (城山 翔斗) is a 1st year student at Yamaboshi High School. He is a member of the school's Jazz Band where is he referred to as "The Prince." Shiroyama has a crush on Iori and Setouchi Kaoru in turn has a crush on him.
Though considered a genius amongst his fellow Jazz members, Shiroyama has displayed a humble disposition and did not show animosity towards the Student Cultural Society despite them both competing to keep Gotou as their respective clubs' advisor.
Shiroyama has black hair and brown eyes and stands at about the same height as Iori. He is typically seen in his school uniform.
- Setouchi Kaoru: Setouchi has a crush on Shiroyama. By the events of Asu Random II, the two have begun dating, but their relationship is put to the test by the phenomenons they face in the Isolation Dimension.
- Nagase Iori: Shiroyama has a crush on Iori and was harshly rejected when he confessed to her. In Asu Random II, the two seems to have good relations and did not think much about the confession that happened.