Agent Elle was originally Dr. Laurel Weaver, who apparently came across dead aliens many times as an NYPD coroner, and had consequently been neuralyzed a number of times. When she adopted the cat Orion, whose collar held the Arquillian galaxy, she became mixed up in the crisis with the EdgarBug. During that affair, Laurel proved that she could make the cut as one of the Men in Black. When Kay retired, Elle was partnered with Jay. There was apparently an attraction between Jay and Elle from the moment they first met.
However, Jay ultimately neuralyzed Elle and sent her back to her job at the morgue. (He claimed she wanted to quit, but his habit by that time of neuralyzing any MiB agent who got on his nerves suggests otherwise.)
After Kay's return, Elle joined the MiB science staff. She often competed with Jay.