They also can happen mid-battle. Seeing your ninja character get hit by a Jack-O-Lantern's Jacknife attack, being stabbed multiple times in mid-air and then thrown to the ground with a bang, only for 'Miss' to appear always makes me chuckle.
Not actually part of the story yet hilarious nevertheless: In Disgaea 3, there's a brand new class called the "Superhero". He not only has one of the largest movement and jump stats in the game, but he can go through enemies much like flying characters. However, there is one oversite in his sprite animations: he doesn't jump. Instead, he merely slides up the wall using his normal standing animation.
Actually, that's what happens with all Flight-type movement characters. Give Asagi her "Sky High" Evility, which gives her the same properties as a flight-type character, and watch her Air Guitar her way up the wall.
The item descriptions. ALL of them. Highlights include (but certainly aren't limited to) the Assassin Bow (Best when fired from a grassy knoll), the Charred Newt (Recovers HP/SP. He didn't get better.), the Trumpet Gun (Be sure to put your lips to the right end) and the Guillotine Axe (Let's not lose our heads over this)
Poison Knuckle: Try not to pick your nose with this.
In Prinny 2, when the Prinnies finally trap the Phantom Thief, he decides to use the Omega Ice Cool spell to summon the Spell Keeper, Joshua. However, instead of instantly unleashing powerful ice magic, she clumsily drops onto the stage, apparently busy reading a magazine, and answers a call on her cell phone. While she does lend the Phantom Thief a little help in the form of random ice magic, she spends the entire battle on the phone!
The "End Turn" Running Gag where the main character gets completely surrounded by the all enemy units and pummeled to death due either to the curiosity or the amusement of the other characters.