Exact be damned, Jeff decided he'd rather try using this thing to randomize his life. He typed, "I wish I would restart life as a different person altogether, and that my new life would be totally random, but that if I feel uncomfortable with it I can go back to my old one by thinking, 'I want to go back to my old life!'"
Sure enough, Jeff felt himself start to regress. He grew younger and younger until he became a newborn, then felt himself get forced back inside his mother's womb and continue to regress until he became a zygote, then was split off into an ovum and sperm which then moved back inside his respective parents' bodies and vanished from existence.
And in two separate lovers, Jeff's essence emerged inside an ovum that a woman's body released and one of the innumerable sperm inside a man's testicles. The man and the woman set about having sex, his penis pounding in and out of her vagina eagerly as their pleasure climbed and climbed. Eventually he came inside her, and the Chronivac's power ensured the sperm Jeff was inside met with the ovum and fertilized it.
Inside this new zygote, Jeff saw the person he'd be in this new life...