Titans, Vol. 1 #38A

Moments of Truth
Epsilon has done substantial damage to Titans Tower, so the Titans take the D.E.O. orphans back to the orphanage - some of them need medical help and there is the possibility that Epsilon will come there seeking revenge on the kid who stole his life - Kevin Tanaka, whose power allowed him to inhabit Epsilon's body for a long time. It turns out Nightwing has suspected Epsilon is not what he appears for awhile now, and has worked with D.E.O. agent Dakota Jamison to learn the truth. Speaking to Kevin they discover it: the real Epsilon was an earlier orphan, and one with serious mental health problems. Kevin, confused, kept possession of him to make him a hero. Sure enough, Epsilon and his lady Theta arrive and battle the Titans. The battle ends with Epsilon seriously injured or dead, and Theta fleeing with him. To win, Kevin had to possess Argent. She was already enraged to learn she was conducting an adult relationship with a thirteen year old, and this is the final straw. She leaves in a cloud of angry words, returns to the wreckage of Titans' Tower and angrily wishes Kevin was dead! And her wish is granted: the strain of holding Epsilon for weeks weakened Kevin's already frail body, and the final possession of Argent put him in a decline from which he did not recover.
Release Date: 2002