You've kept this Rikti embryo fertilized with human DNA as a reminder of an unusual adventure you like to think of as:
It began with a sudden resurgence of Timothy Raymond's memory: he recalled a secret Rikti base in Primeva. You ventured there, and defeated the Rikti inside, but were left with questions. The Rikti leader seemed to remember Timothy, but you had no idea what this might mean.
Timothy's frustration with his lost memory reached a peak then. He decided he was tired of waiting for Arachnos to help him recover his memory. Instead, he sent you to a Circle of Thorns base, where you stole a tome that would help him regain his memories.
The spells contained within the tome worked, and Timothy remembered something more: his DNA had been stolen by the Rikti. He sent you to investigate, and what you uncovered was horrible and fascinating at the same time. The Rikti had used Timothy's DNA to fertilize a number of Rikti embryos. You could only assume his latent psionic gifts were somehow of use to them.
You smuggled the embryos away, and gave most of them to Timothy, who immediately resolved to incinerate them. Before he sent you away, he parted with one final secret, the last thing he had remembered. Rikti were people. Somehow, humans and Rikti shared a common genetic heritage. You're not sure of the full implications of this secret, but you know it's a valuable one.