a product from Wax-Eye and artist Joe Simko that combines his excellent artwork with a horror theme for cereal brands
Wax Eye Cereal Killers are the best trading card series.
A hired fellow-human exterminator --- often a harassassin --- who causes his marks' premature demise by forcing them to eat oatmeal or other grain-based comestible that they absolutely detest, and so said abused victim commits eventually suicide to escape said culinary coercion.
They called Ted Bundy a cereal killer, but I happen to really enjoy hot oatmeal, plain shredded wheat, and other "simple fare" breakfast foods, so Teddy's tactics would have been much less effective at getting me to bite da dust than they would have been with many other folks with more of a "sweet tooth" or "meat 'n' potatoes" meal-selection preference.
One who eats all their friend's cereral at his/her friends house and eats all the cereral at at Walmart without waiting to pay for it.
Person 1: Would you like a snack?
Cereal Killer: do you have cereal?
Person 1: yes...
Cereal Killer: (runs away)
(Comes back with all the cereral his/her friends have and eats it in under 5 minutes)
Someone who who eats NOTHING BUT CEREAL every single day for breakfast and constantly buys cereal and even sometimes steals yours AND IT'S REAL GETTING REALLY FUCKING ANNOYING WHY DID YOU EAT MY CURIOUSLY CINNAMON JIMMY THAT SHIT'S EXPENSIVE AND YOU FUCKING KNOW IT
Employee #1: Damn, didn't that guy buy cereal like last week?
Employee #2: Yeah, but he's a cereal killer.
*Oh btw i don't actually know a guy called jimmy so it isn't an inside joke OKAY!?