Kei backstory: He loved playing with the family of abras and kadabras he helped research and care for, he got along better with them then kids his age, since he was alienated for his awkwardness and for his psychic powers.
There were times he wished he was a pokemon… be careful with what you wish for!
Link
dray-and-erika
(Draygone)
I'm reminded of a story about a kid becoming a Kadabra. It's canon in the games.