Genocyber tells the story of a young girl who has strange powers that make her into an “ultimate biological weapon”, which means she transforms into a demon-like creature that kills everything around her in the most violent way. Incidentally this is the most defining aspect of the whole OVA, the overuse of violence. Heads get smashed, brain matter is flying around and spines get ripped out.
The whole OVA starts with the origin story and awakening of the Genocyber in Hongkong, which ends with the destruction of the whole city, then changes location to tell of a fight between the Genocyber and another biological weapon on an U.S. carrier, which also ends with its destruction. The last two parts of the OVA take place in a dystopic future city in a post-apocalyptic world. It also ends with wholesale slaughter and destruction.
Not that the plot really matters, it feels from the beginning like someone had the concept (a young girl who is the ultimate biological weapon), no idea what to do with it and spun some scarce narrative around slaughter and destruction. And that does work to a degree. The first three episodes that take place in Hongkong and on the U.S. carrier are diverting, while the last two episodes that try to decrease the amount of violence and increase the amount of narration completely fail to entertain. Still, in the end the whole thing feels kinda pointless.