|“||You’ll discover that problems have a way of working themselves out if you talk to your friends.||”|
Ryuuzen Gotou (後藤 龍善, Gotou Ryuuzen) is a teacher at Yamaboshi High School and also acts as advisor to both the Jazz Band and Cultural Research Club. In addition, he is the homeroom teacher of Class 1-C, which includes Taichi, Iori and Inaba. Gotou comes off as a bit lazy and goofy but he can be quite insightful when he wants to be. He likes his students to feel at ease around him, so he allows them to refer to him by his nickname, "Mr. Go".
When Heartseed wishes to communicate with CRC members, he most often takes control of Gotou's body to do so. The reason for this is that Heartseed claims Gotou is one of the few people who won't at all question why they blanked out after being possessed. However, by Yume Random, he realizes the missing memories and wonder whether it was a sleepwalking problem. He even decides that maybe he should go to a hospital to check it out
Gotou can easily be described as laid back and friendly. He rarely takes things seriously and even overlooks his students skipping class. He is depicted as rather lazy and the main characters state he almost never gets involved with their club, a trait they also enjoy. Despite this, Gotou has on occasion shown capable of giving excellent advice to his students.
Gotou is a man of average height and slim build. He has short, unkept black hair and typically dresses in simple button shirts with a tie. He has hints of facial hair along his lips and chin, and has dark-black eyes.
When possessed by Heartseed, his eyes become droopy, his pupils lose their gleam, and is more hunched over than normal.
Gotou was apparently offered a spot on a professional jazz band at some point in the past but he turned the offer down in order to teach physics, which he enjoys.
- Taichi Yaegashi: One of Gotou's students from his 1-C Class. Because Gotou is the advisor of the StuCS, he often interacts with Taichi, and during the Kizu Random arc, Gotou reminds Taichi what it means to be a friend. Unlike most others, Taichi is very polite towards his teacher, though Gotou will occassionally take advantage of Taichi's helpful nature. Taichi seems to be the only member of the Cultural Club that has any respect for him.
- Fujishima Maiko: Because Fujishima is his class's representative and Gotou is, himself, lazy, he often defers responsibilities to Fujishima, such as planning the class trip and other activities.
- Inaba Himeko: Inaba has little to almost no respect for Gotou and frequently throws insults his way, criticizing his laziness. Even so, Inaba is willing to do favors for Gotou, such as handling the class' accounting during the Cultural Festival, which Inaba will often use as leverage in the future.
- He is skilled at playing the saxophone.
- Apparently, Gotou always chokes when he eats hot food.
- Gotou is the only teacher that Inaba does not address respectfully as "sensei".
- In Precious Time, it is revealed that Gotou carries around a box of cigarettes and presumably smokes.