Gon's Big Damn Heroes moment when she used a fire extinguisher on the Hopper Riders.
In the same episode, Yagumura receives a backhand from Worm Mamiya, screaming as he is sent flying.
Tsurugi going through a Heroic BSOD when Kageyama and Yaguruma finds him. Next scene they into a 2-on-1 brawl, in which Tsurugi getting punched into a carwindow with his legs sticking out straight.
Tendo forgetting he challenged Yaguruma into making Tofu when them on the street on the next scene. Tendo goes "Never mind".
After getting punched into the car Tsurugi then for some reason starts hanging out with Kageyama and Yaguruma calling them his brothers while walking down the street with them claiming he will "stand at the top of going to hell" while wearring a top hat and black tailcoat (keep in mind the Hopper Brothers dress like homeless bikers). Latter he gets tossed of a bridge by a worm while screaming for his "brothers" and winds up with his ass stuck in a garbage can and when Tendo finds him Tsurugi says "I will stand at the top of failing, actually I might already be there".
Tsurugi tells a group of Worms that he will show them the magnificent shining blade of his family sword, Discalibur! He then pulls it out, only for the blade itself to be missing. He makes the natural (ForTsurugi) assumption that the blade simply shines too brightly to be seen, and swings the empty hilt at the Worms anyway.
Tsurugi's many silly and futile attempts to woo Misaki count as this and the results. Like when Misaki has enough and lies about her and Kagami being together to get Tsuruji to leave her alone Tsurugi dresses like a cupid and showers them with confetti and congratulates them on being a couple infront of everyone.
The Cooking arc in which whenever someone eats the Worm Chef's food (they don't know he's a Worm), they get... Out of Character, complete with fake wings and and a floating halo. Kagami's father reaction to the Chef (and later on, Tendo's) cooking is downright hilarious, given that he's a stoic father.
Out of Canon Moments
Hyper Battle Video is full is this. Kagami trying to be Tendou is priceless.
Tendo writes Kagami a Badass Boast for him to use by the literal meaning of his name (Arata = Washed. Kagami= Mirror), only for Kagami himself stating it sucks, and Tendo's reaction when he thinks Kagami doesn't wash up.