Otoko Series

The Otoko Series ( 男シリーズ Otoko Shirīzu) is a tetralogy of Drama CDs released for Tengen Toppa Gurren Lagann. It presents a world where the cast of Tengen Toppa Gurren Lagann lives in modern-day Japan, most of them either in attendance of or staffing the Dai-Gurren Academy, dealing with the impending forcible take-over of Japan by America's Teppelin Foundation.

The four parts consist of:
 * Otoko Ippiki Gurren Lagann - Released with the Japanese Tengen Toppa Gurren Lagann Volume 5 DVD.
 * Otoko Do-ahou! Gurren Lagann - Released with the Limited Edition DVD release of Gurren Lagann The Movie: Childhood's End in Japan.
 * Otoko-gumi Dayo! Gurren Lagann - Released with the Limited Edition DVD release of Gurren Lagann The Movie: The Lights in the Sky are Stars in Japan.
 * Otoko no Jouken! Gurren Lagann - Released with the Blu-Ray box set of Tengen Toppa Gurren Lagann.