Most of their race gave up their physicality to become purely spiritual beings. One composite member, however, did not want to abandon the pleasures available to the flesh.
Kelzen, Jirenal and Shanstra, the three segments of that Sensopath, were thus exiled and became scattered through time and tried to reunite. Shanstra wanted to become the dominant personality and absorb all living minds in the galaxy. Not wanting to be subsumed, Kelzen distracted Shanstra through their mental link. This allowed Shanstra to be killed, causing Kelzen and Jirenal to die as well. (PROSE: Infinite Requiem)