Sudou is a classmate of Kubo and Shiraishi. He originally was a member of the environmental committee but had trouble taking good care of the flower beds that were his responsibility.

He has a horrible sense of direction, and can't seem to find Shiraishi when he is standing right next to him.
He is also really good at math but seems to suffer with other subjects, ironically it ended up in him passing all of his exams except math because he forgot to write his name on the paper.

Chapter 34 page 2 He is introduced.
Chapter 34 page 3 talks about how he had trouble taking care of the flower beds.
Chapter 50 page 2 speaks on how he has trouble finding Shiraishi.
Chapter 69 page 5 it talks about how Sudo has a terrible sense of direction.
Chapter 80 page 4 he shows how he got a zero on his math exam but would have gotten 100% otherwise if he wrote his name.