|Full Name||Yamada Sanjuurokurou|
|School||Kisai High School|
|Manga Debut||Chapter 194, pg 4|
Sanjuurokurou has light brown, messy hair with bangs on the right side of his face. He has freckles on his face and is typically seen wearing a button-down over a T-shirt with the number 36 on it.
Sanjuurokurou is a nervous but positive boy who is easily charmed by girls. He is friends with Hitomi, Shousuke, and Ai. He believes that Ai and Hitomi are both vying for his attention, and wonders which girl he should "choose." Shousuke views Sanjuurokurou as "the least-annoying person" he knows.
He is often frustrated by others' inability to remember his first name, and corrects people when possible.
Sanjuurokurou made his first appearance in Chapter 198, where he goes on an outing with Hitomi, Shousuke, and Ai. They visit a coffee shop, an arcade, and a movie theater, and he enjoys himself. In the chapter's omake, he fantasizes about choosing between "tsundere Ai-chan" and "energetic Hitomi-chan."
In Chapter 207, Sanjuurokurou goes to the Komi household for dinner. He is surprised when Komi Shuuko says that he is one of Shousuke's friends. He fawns over each girl who comes over, concluding that Komi Shouko, Ase Shibuki, and Manbagi Rumiko are all great girls. He calls Hitohito Tadano ordinary, and regrets doing so when he realizes that he's Hitomi's brother. He also comes to admire Tadano when he says his name right- this was the first time in the series that any character correctly named Sanjuurokurou.
- His name, Yamada Sanjuurokurou, means "Yamada the thirty-sixth."
- Others often confuse his name with other numbers. In Chapter 198, Ai calls him "Yonjuuichirou" (forty-first), and in the official first popularity poll, his name is listed as "Gojuurou" (fiftieth).
- So far, various characters have called Sanjuurokurou by: Yonjuuichirou (41st), Gojuurou (50th), Rokurou (6th), Juuichirou (11th), Nanajuurokurou (76th), Saburou (3rd), Nijuunirou (22nd), Rokujuukyuurou (69th), Kyuujuuhachirou (98th), and Rokujuurokurou (66th).
- Sanjuurokurou placed 50th in the first popularity poll. His name was jokingly listed as "Gojuurou" for this reason.