#1: While the crab Jikochuu monster attacks Clover Tower, all Alice does is calmly stand and watch, wondering to her butler if she can raise it at home.
Mana lectures the Monster of the Week about its antisocial behavior. The Jikochuu's exasperated expression really sells it.
I read it more as being caught off-guard, but either way, it's amusing. It just stands there, too, as she tries to transform in a much Kamen Rideresque way.
The Crab Selfish itself and the overall pettiness behind it's rampage is pretty funny. "Screw the lines!"
Nikaidou suggests to Momota that they should cut the lines so they can go up faster...only to give up on it after Mana calls them out. Just a second after he said so.
#2: Mana's reactions to Rikka commenting on how they didn't have a chance to talk, that she still didn't know what the former was hiding, but that Rikka expected Mana to be honest, if she ever decided to talk. The music makes it even more amusing.
Another one comes when Rikka retorts on Mana confessing being a Precure. The fact that she does with a completely straight-face makes it a real riot.
#4: The episode's second Monster of the Week makes its first appearance by rapping about its lunch. Then we get this exchange.
Rikka: It's a boombox!
Mana: What is that?
The way the first one is defeated counts too: its batteries run out.
#8: Mana's horribly-sung lullaby for Ai-chan, and Rikka and Alice's reaction to it.
#9: Ira summons two Jikochuus at once, but they constantly arguing each other (the two victims were bickering over who gets to use the playing field). Cure Heart even blows a whistle because they don't listen to her.
The soccer ball Jikochuu attacks Cure Heart and Diamond with a soccer ball who are about to guard themselves, but while it attacks with the second ball it lectures them that using the hands is illegal. That irritates them for one second and they gets hit off-guard.
As Ai-Chan wandered around the school and the fairies followed, Ai-Chan caused weird things to occur across the school. The statues in the art department came alive, the gym equipment started moving on their own, portraits of Beethoven, Mozart and Chopin began singing, and books in the library flew around. Obviously this didn't sit well with the students; Mana was informed that it was the result of ghosts, and one student even reported a demonic ritual involving three "pink, blue and yellow monsters" that said "Sharuru," "Keru," and "Lansu" occurred in the library. One guy suggested it was the start of the school's seven mysteries, and added the next could come from the bathroom. It's way funnier to watch than read what it looks like in text.
#10: The Selfish formed from the "pure" heart of a Makopi fanboy, confirming to every obsessive paedophile stalker stereotype, shows just how unbelievably pathetic the adult-male Idol Singer fanbase is. There is no other way to describe it.
#11: Bel's terminally moronic beast form, nothing more than a giant flip phone with his face as the screen. Ditto with Ira's yellow elephant beast form in the following episode; Makoto, Alice and Rikka even say that he looks cute.
#12: The boy Jun describes Mana as a white horse riding prince, then he says he wants to become that manly like Mana. Rikka comments that Mana isn't a man.
#20: While the Precures effortlessly scale the icy cliff in literal leaps and bounds, poor Joe is left behind huffing and puffing like a racehorse. He politely declines the girls' offer to give him a helping hand out of embarrasment at the situation.
#21: After Cure Heart saved Regina from commitin a Heroic Sacrifice, Bel yells they should fall in the pit of lava. Heart's yelled response: "I REFUSE!"
#22: The frozen frame of the girls building a sand castle and Regina just intentionally spilling a bucket of water on it. Makopi's face saying "I'm not amused" - Alice however is.
The Report Jikochuu asks Heart whether she has a boyfriend. Her response: "Huh?" Then, it asks Diamond what score she reached in her last test. Her response: "It's not your business!" And then, it asks Rosetta how much money she has. Her response: "Oh well, I never count."
#25: Mamo's dumbfounded expression as she transform with Sebastian's Cure Commune.
Lance showing Sebastian how to use female beauty product and Sebastian fascinated reaction to it.
#32: Aguri's lecturing Juujou and the rest of festival commitee about their uselessness, especially how Aguri delivers it. When Rikka later asked them what's going on, they're shown in a typical Played for Laughs depression.
Nikaidou's promoting his class' booth in a very unmotivated manner. Lampshaded by Yashima.
#33: The whole chase shown in Alice's flashback. Alice's father and his servants chased the girls, but Rikka had analyzed the whole mansion with something that looked like a tablet and she knew all secret tunnels and traps.
#39: Regina's evil speech is interrupted by Mana's GLOMP.
Also, whenever Bel checks on his Jikochuu monster, Cure Ace is just casually kicking its butt like no one's business. Considering what's going on between Cure Heart and Regina at this point and then suddenly transitioning to this, the irony is subtle, yet hilarious.
Joe who is Bel in disguise, makes takoyaki for the girls and the mascots, only for them to angrily berate him for not putting any tako (octopus) in the takoyaki. While all of their reactions are funny, Lance's takes the cake.
This later comes back to haunt him as when the girls reveal they knew that Joe was a fake, Lance uses a takoyaki allusion.
Aguri: So that means...
Alice: You're exactly like the takoyaki without octopus.
#49: The images shown when Cure Heart explains to the Proto-Jikochuu how he can't be selfish when nobody's around. Mood Whiplash indeed.
This one borders on Toilet Humor, during Cure Heart's "I'm Selfish, But I Have Friends" speech, it looks like Proto-Jikochuu like a human trying not to barf up his lunch. Furthermore, despite trying to fight it, when he finally succumbs to the purification, the big scary uber-powerful Big Bad goes out involuntarily shouting "Love, love, looooove!!" just like the standard Monsters of the Week did.