Ao no Miburo: Serizawa Ansatsu-hen

Season 2. Adapts up to Chapter 122. To continue, start at Manga Volume 15 (Chapter 123), which is also Volume 1, Chapter 1 of the 'Shinsengumi Arc' sequel manga. Note: While some sources merge the series, they are technically separate. The anime is a faithful adaptation, only omitting minor comedic reaction shots.