Master post and guide for finding chapters of World ... - Tumblr
Pick up the manga at Chapter 42 (Volume 11).
(Season 2) — 12 Episodes.
To truly understand the complex master plans of characters like Guren Ichinose and Ferid Bathory, reading the prequel light novels is highly recommended by fans on the Owari no Seraph Wiki.
(OVA) — An episode focused on the backstories and lighthearted moments before the main plot.