Ryuu Seiki
English title: Dragon Century
Japanese title: 竜世紀
Type: OVA
Episodes: 2
Source: Unknown
Genres: Action, Fantasy, Sci-Fi
Studios: AIC
Duration: 27 min per ep
Rating: R - 17+ (violence & profanity)

The story of a young girl and a young dragon. Naturally, they are the best of friends, and naturally the rest of the world is against them both. However, when demons decide to trash their world, they side with those who have always been against them.

(Source: AniDB)