List of High School DxD episodes
High School DxD (2012)

Series no.
Season no.
Title
Director
Writer
Original airdate
1
1
"I Got a Girlfriend!" Transcription: "Kanojo, Dekimashita!" (Japanese: 彼女、できました!)
Taro Kubo
Takao Yoshioka
January 6, 2012
2
2
"I'm Done Being Human!" Transcription: "Ningen, Yamemashita!" (Japanese: 人間、やめました!)
Kazuhide Kondo
Takao Yoshioka
January 13, 2012
3
3
"I Made a Friend!" Transcription: "Tomodachi, Dekimashita!" (Japanese: 友達、できました!)
Kosuke Kobayashi
Takao Yoshioka
January 20, 2012
4
4
"I'm Saving My Friend!" Transcription: "Tomodachi, Sukuimasu!" (Japanese: 友達、救います!)
Masayuki Iimura
Takao Yoshioka
January 27, 2012
5
5
"I Will Defeat My Ex-girlfriend!" Transcription: "Motokano, Taoshimasu!" (Japanese: 元カノ、倒します!)
Tetsuya Yanagisawa
Takao Yoshioka
February 3, 2012
6
6
"I Work as a Devil!" Transcription: "Akuma, Yattemasu!" (Japanese: アクマ、やってます!)
Akira Shimizu
Takao Yoshioka
February 10, 2012
7
7
"I Get a Familiar!" Transcription: "Tsukaima, Getto Shimasu!" (Japanese: 使い魔、ゲットします!)
Takenori Mihara
Takao Yoshioka
February 17, 2012
8
8
"I Pick a Fight!" Transcription: "Kenka, Urimasu!" (Japanese: 喧嘩、売ります!)
Koji Kobayashi
Takao Yoshioka
February 24, 2012
9
9
"I've Begun My Training!" Transcription: "Shugyō, Hajimemashita!" (Japanese: 修行、はじめました!)
Kosuke Kobayashi
Takao Yoshioka
March 2, 2012
10
10
"The Showdown Begins!" Transcription: "Kessen, Hajimarimasu!" (Japanese: 決戦、始まります!)
Masayuki Iimura
Takao Yoshioka
March 9, 2012
11
11
"The Acclaimed Battle Continues!" Transcription: "Zessan, Kessenchū desu!" (Japanese: 絶賛、決戦中です!)
Taro Kubo
Takao Yoshioka
March 16, 2012
12
12
"I'm Here to Keep My Promise!" Transcription: "Yakusoku, Mamori ni Kimashita!" (Japanese: 約束、守りに来ました！)
Tetsuya Yanagisawa
Takao Yoshioka
March 23, 2012

Question: Who wrote for High School DxD? When did it air?
Answer: High School DxD episodes were written by Takao Yoshioka and aired from January 6, 2012 to March 23, 2012.