Lester is an annoyingly bratty (yet somehow sweet) incest-hybrid. He was a complete mistake from lack of education between his parents. He'll often fall asleep on his Father's head, or try to eat his mother's sleeves.
He's mostly a daddy's boy.
In the final fanon version, Lester was born in a random place. (Most likely at Foop's castle in the middle of the night because he be trollin'.)
Like most Anti-Fairy babies, he was able to talk immediately after his birth.
He quickly realized that annoying adults was fun. He would steal his grandfather's monocle to annoy him, knock over his great grandfather's cheesecake, or just annoy people in general.
Lester met Cecily at a playground, as her orphanage was taking a feildtrip thing. Since he's a derp, he quickly thought her bossiness was a joke, and became friends with her.
Sidney wasn't too happy about this, though. Since she didn't want to lose her son to a girl yet. Because she's an overprotective freak.