An original video animation or OVA is a type of Japanese animated film or series made for release in home video markets. These animations sometimes appear on TV, but more often than not they are direct-to-vieo (at least, in the old days). While they often had a higher budget than a standard anime episode, the quality was not always so good (especially during the 1980's, when direct-to-video was so sought after that anyone with money could commission something like this). OVA often accompany an anime, manga, or game, and could sometimes serve as a pilot episode for an anime adaptation of a manga. While OVA still exist today, it seems more likely that anime movies will be adapted instead.
It seems pretty common for games to get an OVA at some point in their lifetime. The visual novel series Houma/Jewel BEM Hunter Lime received an OVA in the 1990's, as well as the original Fire Emblem. Interestingly enough, the Fire Emblem OVA was dubbed into English, despite the original game not being (officially) translated for overseas audiences until about 2021.
The lack of TV restrictions also greatly helps the creative freedom of this type of animation. Games like Eimmy to Yobanaide/Amy's Fantasies have received an OVA, as well as the eroge Rance, based off its newer canon. Some very famous manga have also received an OVA before officially receiving an anime, with one famous example being JoJo's Bizarre Adventure: Stardust Crusaders. I believe there was an OVA made for Phantom Blood as well, but it's been lost media for basically ever. Devilman by Nagai Go has also received multiple OVAs.
Of course, due to the saturation of the market, there have been some really bad ones, too. And that's where I come in! A good friend of mine and I like to sit down and watch whatever OVA we can find that either seem really ridiculous or really awful. While some of them turn out to be really good, a lot of them are poor quality in their own unique ways. We should be thankful that something like Chargeman Ken never had the budget to receive a proper OVA, although its predecessor could theoretically count as one (alas, it is a special).
