OVA titles have a reputation for detailed plots and character-development, which can result from the greater creative freedom offered to writers and directors relative to other formats. This also allows for animated adaptations of manga to reflect their source material more faithfully. Since OVA episodes and series have no fixed conventional length, OVA directors can use however much time they like to tell the story. Time becomes available to expand upon significant background, character, and plot development. This contrasts with television episodes (which must begin and conclude in 22 to 26 minutes) and with films (which rarely last more than two hours). In the same way, no pressure exists to produce "filler content" to extend a short plot into a full television series. The producers of OVA titles generally target a specific audience, rather than the more mass-market audience of films and television series, or may feel less constrained by content-restrictions and censorship (such as for violence, nudity, and language) often placed on television series. For example, the Kissxsis OVA series generally contains more sexual themes than its television counterpart.
The earliest known attempt to release an OVA involved Osamu Tezuka's The Green Cat (part of the Lion Books series) in 1983, although it cannot count as the first OVA: there is no evidence that the VHS tape became available immediately and the series remained incomplete. Therefore, the first official OVA release to be billed as such was 1983's Dallos, directed by Mamoru Oshii and released by Bandai. Other famous early OVAs, premièring shortly thereafter, were Fight! Iczer One and the original Megazone 23. Other companies were quick to pick up on the idea, and the mid-to-late 1980s saw the market flooded with OVAs. During this time, most OVA series were new, stand-alone titles.
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