A young man named Akitsu Masato is captured by a secret govt. project known as "Last Guardian". He is told that his life as a normal student was all a lie, and that his real destiny is to be the pilot of a great robot called "Zeorymer of the Heavens". The truth of this is hammered in when Masato sees his parents accept payment for raising him. The Last Guardian is preparing for the resurrection of "Hau Dragon", an organization bent on world conquest. 15 years ago, Hau Dragon built 8 great robots. Each of the mecha represents a force of nature. However, before any of the robots could be used, their creater Kihara Masaki destroyed the robots except for the leader: Zeorymer. He took Zeorymer and an embryo to the government. The embryo became the boy Masato. Now, Hau Dragon has rebuilt the other 7 mecha and wants the 8th. It will be up to Masato and Himuro to pilot Zeorymer and fight against the Hau Dragon, but neither Masato or Himuro are all that they seem. (Source: AniDB)

Data xx Transitory is the thirteenth and bonus episode of the DRAMAtical Murder animation. It features all of the bad endings from the original game.

The seal which was imprisoning the fallen angels, Kirin no Yuda and Houou no Ruka, is broken and the two decide to get revenge on the God who had cast them to Hell by getting rid of the Heavens that had once been their home. Soon the guardian angels on Earth begin disappearing, and no one in Heaven can explain the happenings. But there is a sense of a vengeful animal spirit at work, and so the four Saint Beasts are called upon to investigate. The 4 Gods of Beasts attempt to rescue the guardian angels, as well as to find out what this evil animal spirit is... (Source: Wikipedia)

This was shown as part of the "Jump Super Anime Tour" of October 1994, prior to the Ninku TV series.