Doctor Clay is a character with a shady past. Not much is known about him except that he was once a student in the same academy that Washu went to. Unfortunately for Clay, he was kicked out of the Academy. He blames Washu for his dismissal from the academy, but the real reason comes out when Washu describes what happens. " People who don't like their work are disliked and are kicked out of the academy." After 20,000 years, Dr. Clay gets a chance to meet the genius scientist Washu again. This is because he is sent on a mission by the Lady Tokimi to bring the Lady Washu to her. Clay is eager to do this mission because in return, Lady Tokimi will grant Dr. Clay ruling rights to an entire galaxy.
After this, Dr. Clay sets out to complete the mission that was set forth by the Lady Tokimi. He decides to duplicate Ryoko by using Zero and then use the new Ryoko to capture Washu. The duplication process was not a complete success, however. Dr. Clay was able to duplicate everything about Ryoko except for her power gems. So, Clay tells Zero to take the power gems from the real Ryoko and complete the mission. Zero tries time and time again to capture Washu, but to no avail. Every time Zero tries to capture Washu, Tenchi ruins everything. Dr. Clay, being a scientist, realizes this and tells Zero to get rid of Tenchi. This was not to be because when Dr. Clay decided on duplicating the real Ryoko, he also duplicated the emotions that Ryoko had for Tenchi. Thus, Zero fails to kill Tenchi in his bedroom. Zero's identity revealed, Washu, Tenchi, Aeka, and Mihoshi go and try to get the "real" Ryoko back. Dr. Clay is able to meet Washu again on his ship. They start conversing and more is known about the doctor. First of all, when the two of them were in the Science Academy, they were both going for "Director Chair". It is also known that Dr. Clay marks everything that he holds dear with a special emblem. This is how Washu was able to discover Zero and find the entrance to the bridge of Dr. Clay's ship. Dr. Clay finds out that Zero betrays him for Tenchi so he sets a self destruction of his ship and escapes in a small vessel. Tenchi and the gang survive the black hole that the destruction of the ship made, by the creation of the Light Hawk Wings. From a distance, Dr. Clay witnesses this, and decides to go back and tell Lady Tokimi. Unfortunately, his vessel crashes into Ryo-Oki and he is put into custody by the Galaxy Police. We are left with the information that Lady Tokimi's assistant will have "to do something about Dr. Clay".