|Homeroom Teacher||Hirata Ryouko|
|Seiyū||Yamazaki Haruka (山崎 はるか）|
|Anime Debut||Episode 2|
Kaidou (海道) is a friend of Kiriyama Yui who is seen eating lunch together with Kurihara Yukina.
- Kaidou only makes an appearance in the anime (episode 2 and 9).