Alric, the Obstagoon, and his obsession with Pokemon that start with Z.
It's his favorite shirt that he wears all the time, and even if he's never seen a specific Pokemon before, he will know if their species starts with the letter Z.

Example: Zangoose.

Alric is not exactly an antagonist, but he's kinda messed up in the head and in constant conflict with himself.

He's a highschool dropout that's a couple years older than Aladar and a few inches taller.
His obsession with the letter Z causes his parents and others to worry about him while he's out. Though he's mostly fine, when his "Z is life" starts acting up, he can get a bit out of control, and do things he normally wouldn't.

Though he has a job at a radio station, he does take part of some sketchy drug business practices.
He's also a smoker. He doesn't smoke when his "Z" condition takes over, but usually has a cigarette or E-cigarette in his mouth.

Here's where the "Not exactly an antagonist, but" part kicks in:

Alric has the severed tail of Zamazenta hidden in the drawers of his room.
Of course he himself didn't cut off Zamazenta's tail, but he did buy it off of the (Real antagonist) who did. It was purchased while he wasn't in the right mind, and he feels guilty and wrong for having it, but well, to him, Z is Life and all...
He snuggles with it every night.

Though he'll like basically anyone who starts with Z; Zamazenta is the guy he has the biggest crush on.
Alric is a good guy, but he has had some offers of ways he could make Zamazenta his. Ones that any normal person would turn down in a second due to moral reasons.
He wants to get close to Zamazenta, but he wants to do it without his Z condition getting in the way, and fears he might lose control and mess up real bad.

His life his rather complex sometimes, and smoking helps him keep his cool most of the time.

Oh yeah, and he's had plenty of "Not my proudest fap" kind of moments.
He's pansexual after all, so in his eyes (Which are yellow btw), all that start with Z are worthy of his love.

 naughtybigdog