Info:
Hakuōki (薄桜鬼 〜新選組奇譚〜 Hakuōki ~Shinsengumi Kitan~) is a video game series by Idea Factory for the PS2/PSP/PS3/DS/3DS platforms. It has been adapted into two 12/10-episode anime series animated by Studio DEEN. The series has also been adapted as two different manga series. A third series based on the prequel, Hakuouki Reimeiroku, is scheduled for Summer 2012. Two new movies are scheduled for 2013.

Story:
Chizuru Yukimura heads to Kyoto to search for her father. While there, she witnesses a fight between Rasetsu and members of the Shinsengumi. The Shinsengumi take her into custody and, once learning she is the daughter of the doctor they are searching for, decide to keep her close at hand.

Novel adaptation:

小説 薄桜鬼 壱(1)
小説 薄桜鬼 弐(2)
小説 薄桜鬼 参(3)
小説 薄桜鬼 四(4)
Hakuouki Shinsengumi Kitan part1 (薄桜鬼 〜新選組奇譚〜 ストーリーブック 上巻)
Hakuouki Shinsengumi Kitan part2 (薄桜鬼 〜新選組奇譚〜 ストーリーブック 下巻)
薄桜鬼 随想録 ストーリーブック 上巻
薄桜鬼 随想録 ストーリーブック 下巻
Hakuouki　Reimeiroku part 1 薄桜鬼 黎明録 ストーリーブック 上巻
Hakuouki　Reimeiroku part 2 薄桜鬼 黎明録 ストーリーブック 中巻
Hakuouki　Reimeiroku part 3 薄桜鬼 黎明録 ストーリーブック 下巻
Hakuouki Sekkaroku　~Night~（小説 薄桜鬼 雪華録 ~宵~）
Hakuouki Sekkaroku　~Day~　（小説　薄桜鬼 雪華録 ~明~）

Manga adaptation:

薄桜鬼アンソロジー 紅
薄桜鬼アンソロジー 蒼
薄桜鬼アンソロジー 焔
薄桜鬼アンソロジー 凛
Hakuouki Junrenka1　薄桜鬼 巡恋華 1
Hakuouki Junrenka2　薄桜鬼 巡恋華 2

Anime Adaptation：

First Season: (12 episodes)
Hakuouki: Shinsengumi Kitan
Second Season: 1 recap +(10 episodes)
Hakuouki: Hekketsuroku
Third Season: (12 episodes)
Hakuouki Reimeiroku

The second season continues the numbering from season one; therefore, episode 1 of the second season is episode 13. Similarly, there was a recap episode of the first season aired the week before episode 13, called episode 00. The third season is a prequel to the series.

Hakuouki Sekkaroku OVA: (薄桜鬼 雪華録) 6 chapters
-第一章 玄夜の白雪 (Okita Souji)
-第二章 冬の埋み火 (Hajime Saitou)
-第三章 空裂く槍 (Harada Sanosuke)
-第四章 揺蕩う舟 (Toudou Heisuke)
-第五章 天明の風 (Hijikata Toshizou)
-第六章 雪華の舞 (Kazama Chikage)

Other media:
Character Smartphone apps (6)
薄桜鬼VISAカード (Hakuouki VISA CARD -- a tie-up of Idea Factory + Sumitomo Mitsui)

Source:Wikipedia