Saijaku Muhai no Bahamut
English name: Undefeated Bahamut Chronicle
Genres: Action, Fantasy, Romance, Ecchi
Type: TV, Episodes: 12
Aired: Jan 11, 2016 to Mar 28, 2016
Studio: Lerche
Source: Light novel
Rating: PG-13 - Teens 13 or older
Synopsis:
Lux, a former prince of an empire named Arcadia that was overthrown via a rebellion five years earlier, accidentally trespasses in a female dormitory's bathing area, sees the kingdom's new princess Lisesharte naked, incurring her wrath. Lisesharte then challenges Lux to a Drag-Ride duel. Drag-Rides are ancient armored mechanical weapons that have been excavated from ruins all around the world. Lux used to be called the strongest Drag-Knight, but now he's known as the "undefeated weakest" Drag-Knight because he will absolutely not attack in battle. After his duel with Lisesharte, Lux ends up attending the female-only academy that trains royals to be Drag-Knights.

(Source: ANN)