[[caption-width-right:300: A rather unlikely friendship.]]

->'''Satan:''' Put your socks on, Leo! We're goin' out!

''Leo and Satan'' is an animated comedy created by {{Newgrounds}} user Oney (Chris O'Neill), featuring the exploits of Leo, a preteen boy with a trapdoor to hell in his bedroom, and {{Satan}}, who's [[ExactlyWhatItSaysOnTheTin exactly who you'd expect him to be]], although for the dark lord, he's pretty chipper and childish (but also quite bipolar).

The unlikely duo's first appearance, "[[http://www.youtube.com/watch?v=OchjFx3YgEE Leo and Satan Pancake Doomsday]]", is a simple introduction to Leo's love of pancakes and Satan's love of sugar. Nothing special.

"[[http://www.newgrounds.com/portal/view/530334 Leo and Satan Algebra Aversion]]" is considered the first full episode, in which Leo's struggling with his math homework. Satan tries to help out, with disastrous results.

"[[http://www.youtube.com/watch?v=puy52LVqG7c Leo and Satan Sugar Trip]]" is an overall improvement on length, animation quality and humour, as the pair discover to their horror that they're out of sugar. Whilst walking through town, they bump into a shady man who has what they need...

"[[http://www.youtube.com/watch?v=cHgIQYvv9kk Leo and Satan Trash Hazard]]", has the couple ''borrow'' a board game from the neighbor's trash, which turns out to be a Ouija board.

"[[http://www.youtube.com/watch?v=icXGswYLHSs Leo and Satan - Battery Catastrophe]]" has the duo trying to find the batteries for their game controller.

"[[http://www.youtube.com/watch?v=HHA6J7Nvu0Y Leo and Satan - Leo Goes to School]]" It's Leo's birthday, and that means it's time to start going to school.
!!This web cartoon provides examples of:

* BackFromTheDead: [[spoiler:Apparently, if Leo dies, he'll just go to hell, climb up a tall mountain, and come out through a trap door in his bedroom.]]
** Also, Leo's [[spoiler:parents, who were killed by Satan a few episodes ago.]] The jury's still out on whether or not this is actually a good thing, considering they're both now BuriedAlive and gasping for air.
* ChekhovsGun: [[spoiler:The trapdoor that connects hell and Leo's bedroom.]]
* CreatorCameo: The drug dealer in "Sugar Trip" is Sean Kiely. [[http://www.youtube.com/watch?v=4-OY76Na8sc He even wears the same garb and uses the same voice in an update video]].
* DeathIsCheap: When you consider that there is a [[spoiler: magic trapdoor leading from hell to Leo's bedroom...]]
* DidWeJustHaveTeaWithCthulhu?: Satan is a [[spoiler:a house-sized red horned dragon]], and well he is Satan.
* ElmuhFuddSyndwome: Leo, at least sometimes.
--> '''Satan:''' "Lemme help you with that math homework!"
--> '''Leo:''' "Wow, Satan, that wud be t-t-tewwific!"
* EverybodyHatesMath: Satan tries to help Leo with his Algebra homework... it doesn't go very well.
* EvilSoundsDeep: [[RecurringCharacter Esquire]], the creepy stranger who first appeared in Sugar Trip, has a very deep, growly voice. It's not really a man that you would like to meet.
** Also Satan, when he gets furious.
* ExactWords: Leo's birthday wish is for his dead parents to come back to life. Cue shot of said parents' grave with muffled screams coming from it.
* MoodSwinger: Satan is prone to them.
* IncrediblyLamePun: "Trash Hazard":
-->''[after Satan crashes through the window]''
-->'''Leo:''' Whoa Satan. Looks like your stealth is out the window! *smile*
-->'''Satan:''' ...shut the fuck up, Leo.
* NightmareFace: Satan does this a LOT.
* NumberOfTheBeast: [[spoiler:The answer to Leo's math problem in "Algebra Aversion"]]
* OuijaBoard: In "Trash Hazard".
* PrecisionFStrike: "I DON'T FUCKING KNOW. GOD."
* PromotionToParent: There's enough evidence to suggest that Leo's sister is also his legal guardian. She's the only person he ever mentions when concerned about getting yelled at by an adult, not to mention that the only reference to his actual parents involves them being BuriedAlive.
* {{Satan}}:
* SpeechImpediment: Both Leo and Satan are affected by this when they speak.
* ShoutOut: [[TheExorcist "The power of Christ compels you!"]]
** {{Irony}}: Satan said that line.
* TheStinger: "Trash Hazard": [[spoiler:"Now how the heck did I end up in here?"]]
* WhatTheHellIsThatAccent: Satan speaks in what can only be described as an infernal bastardization of a Jamaican accent or maybe "Hiberno-Ali-G-Carribean" with a sprinkle of Briticisms. Leo's accent tends to [[OohMeAccentsSlipping vary from scene to scene]], sometimes approximating Satan's accent, sometimes sounding somewhat Irish (which is the least surprising, considering that the Series' creator is Irish) and sometimes sounding generically American.