Trey Parker's Japanophilia is on full display in an episode-long Affectionate Parody of shonen anime.
The boys are roaming the Park County Fair when they spot a knife stall selling Japanese ninja weapons. Roger, the proprietor, says he cannot sell them weapons without a parent present, so the boys pretend to be orphaned brothers and turn on the waterworks to get Roger to relent; Stan buys a pair of tonfas, Kyle a pair of nunchaku, Cartman a pair of sai, and Kenny a pair of shurikens. After a practice session using the weapons in Cartman's basement, they assume ninja identities (complete with Art Shift to a more Animesque style) and show off their new weapons to Craig, Token, and Clyde. But when they run into Butters, they tell him he can't play ninjas with them; stung by their rejection, he returns home and dons his supervillain alter ego, Professor Chaos, before confronting the four ninjas. A parody of anime fight scenes ensues... and Reality Ensues when Kenny throws a shuriken that embeds itself in Butters' eye.
Unfortunately for Butters, the boys shy away from taking him to the hospital for fear that their parents will find out they bought ninja weapons behind their backs, but when an attempt to remove the shuriken themselves fails, they come up with Plan B: disguise Butters as a dog and take him to the (very short-sighted) veterinarian. But as they are escorting the increasingly woozy and incoherent Butters to the vet, they run into Craig, Clyde, Token, and Jimmy, who have used the "orphaned brothers/waterworks" scheme on Roger as well and now have their own ninja weapons. Hiding Butters in an old oven, Stan, Kyle, Cartman, and Kenny do battle with the other four ninjas... until they notice Butters has wandered off. Now all eight boys must find him before his injury leads their parents to discover their illicit weapon purchases.
Butters finally arrives at the hospital, but the emergency staff are fooled by his dog disguise and call the animal shelter. Deciding that the "dog" is beyond medical help, the shelter decide to put him to sleep, but he escapes again. Meanwhile, Stan, Kyle, Cartman, and Kenny try to get rid of the evidence of their crime by returning their weapons (which Roger won't permit) when Craig, Clyde, Token, and Jimmy say they've seen Butters at the fairgrounds - on the opposite side of a big auction which all of their parents are attending. Cartman declares that he can use his ninja invisibility to sneak past the auction and keep Butters from being discovered; unfortunately, Reality Ensues again as his "invisibility" just involves stripping off and trying to sneak nude across the stage in front of a shocked audience. To add insult to injury, Butters wanders onto the stage, Kenny's shuriken still in his eye, and passes out.
At a community meeting, the townsfolk are outraged... by Cartman's public nudity. Stan, Kyle, and Kenny are amazed that the adults don't care about their weapons, so they join in the condemnation of Cartman's streaking, then leave to resume their ninja escapades.
Good Times with Tropes:
- Affectionate Parody: Of shonen anime and background songs, especially nonsensical ones.
- Art Shift: The fantasy sequences would often cause the episode to shift to an Animesque art style.
- Bilingual Bonus: "Let's Fighting Love" is full of these; the first verse sees the singer boasting about his genitalia, while the second verse points out how ridiculous the lyrics are. Notably, the entirety of the song is in authentic Japanese (which Trey Parker speaks fluently), as opposed to foreign-sounding gibberish.
- Blatant Lies: Cartman tries to blame his nudity on a Wardrobe Malfunction. No one buys it.
- Did Not Think This Through: Cartman probably wouldn't have stripped naked had he remembered the kids were only pretending to be super-powered ninjas and he doesn't actually have the power of invisibility.
- Everybody Cries: Stan, Kyle, Cartman, and Kenny use a sob story, complete with Crocodile Tears, to convince a vendor at the county fair to sell them their ninja weapons. Apparently, they've done this to get their way 11 times prior.Stan: God damn, that's like the 12th time that's worked.
- Eye Scream: Butters gets hit in the eye with a shuriken, setting off the episode's main conflict.
- Getting Crap Past the Radar: Read the lyrics to "Let's Fighting Love."
- Gratuitous Japanese: "Let's Fighting Love," with a bit of Gratuitous English thrown in.
- Humiliation Conga: In order to disguise his identity, Butters is forced to pretend to be a dog and then gets urinated and defecated on by actual ones. And this is after the Eye Scream mentioned above.
- Invisible Streaker: One of Cartman's "many, many powers" as a ninja is the ability to turn invisible, albeit with the caveat that his clothes don't follow, hence why he strips naked at the end. Unfortunately for him, he doesn't have any powers in the real world, so all he accomplishes is just getting naked in front of everyone.
- Karma Houdini: Stan and Kyle face no repercussions for not helping Butters deal with his eye injury. While he does get punished for something else, Cartman also does not face extra punishment for that. However, Kenny stands above them all, as he was the one who gave Butters the injury. He doesn't even come close to dying in this episode!
- Lampshade Hanging: Later in "Let's Fighting Love," the lyrics lampshade the song's nonsensical dialogue. Translated from the Japanese (except for the last six words, which are in English in the original):This song is a little stupid
It's hard to make sense of
The English is all messed up
That's okay, we do it all the time!
- OOC Is Serious Business: After Kenny throws a shuriken into Butters' eye, Kyle is so terrified of what his mother will do to him if she found out he was playing with weapons that he actually agrees with Cartman they they should kill Butters and hide his body rather than get him medical attention.
- Reality Ensues:
- The stylized anime battle between the boys and Professor Chaos. The make-believe fireballs and energy blasts aren't working, so Kenny tries his magical shuriken and scores a direct hit on Professor Chaos. Cut back to the normal art style, with poor Butters shrieking in pain and terror while blood streams from the throwing star in his eye.
- During the climax, the boys discover that Butters is at the auction and is in danger of exposing his injury to the parents. Cartman decides to save him by turning invisible while naked. This only works in the anime art style, however — the normal animation shows that he just walks across the stage naked, causing a much bigger controversy than Butters's injury.
- Shout-Out: The boys ninja/anime forms are basically Street Fighter characters. Stan looks like Ryu, Kyle resembles Fei Long, Cartman is E Honda, Butters resembles M Bison combined with Sagat, Jimmy is Sodom, Clyde is Adon, Craig is Guy, and Token is Dee Jay. Kenny is the odd man out here, as he resembles Raiden from Mortal Kombat. Also, Chef resembles Akuma.
- Skewed Priorities: The townspeople are more upset at Cartman running around naked than Butters nearly losing his eye, ultimately forgetting about the latter and allowing the other boys to get off scot-free for what they did.
- Teeny Weenie: Cartman's penis is shown to be very shriveled up and minuscule. That stands to logic because being obese makes your penis look a lot smaller. There's also that fact that's he's still a kid.
- Vocal Dissonance: None of the boys' voices change, even when they're drawn to look like big, burly ninjas.
- Weapon of Choice: The boys all form their own distinct ninja personas based on the weapons they're wielding.