Strike the Blood - Season 1 - Eps 16: Fiesta for the Observers I
Kojou comes out of the battle with his own body back, but both Yuuma and Natsuki have fallen. The true prison barrier has been revealed along with Yuuma's mother, Tokoyogi Aya, and the other magic criminals who were incarcerated within.
About Strike the Blood

Title: Strike the Blood
First Air Date: 2013-10-04
Last Air Date: 2022-07-29
Status: Ended
Rating: 6.9/10 (from 65 votes)
Language: JA
Seasons: 6
Total Episodes: 58
Network: AT-X
Genres: Animation, Action & Adventure, Sci-Fi & Fantasy
Production Companies: CONNECT, KADOKAWA, SILVER LINK., BARNUM STUDIO, movic, Warner Bros. Japan, ASCII Media Works, THE KLOCKWORX, Hakuhodo DY Music & Pictures
Synopsis
Kojou Akatsuki's days as an ordinary high school student in the Demon District of Itogami Island come to an abrupt end after a fateful encounter leaves him with the remarkable abilities of a vampire. It isn't long before he is thrust into the center of attention when it is discovered that he is the fourth primogenitor, an immensely powerful vampire whom most consider to be merely a legend. Fearing Kojou's destructive potential, the Lion King Organization sends in an apprentice sword-shaman, Yukina Himeragi, to monitor, and should he become a threat, kill the boy deemed the world's most powerful vampire. Forced together by circumstance, the two form an unlikely alliance as Kojou comes to terms with his abilities and they both struggle to protect the city from various emerging chaotic forces.
Cast

Yoshimasa Hosoya
Kojou Akatsuki (voice)

Risa Taneda
Yukina Himeragi (voice)

Asami Seto
Asagi Aiba (voice)

Rina Hidaka
Nagisa Akatsuki (voice)

Ikumi Hayama
Sayaka Kirasaka (voice)

Ryota Osaka
Motoki Yaze (voice)

Hisako Kanemoto
Natsuki Minamiya (voice)

Kanae Itou
Kanon Kanase (voice)

Yuka Iguchi
Astarte (voice)

Sayaka Senbongi
Yuiri Haba (voice)