Subverted Kids Show / Anime & Manga

• Bokurano. A bunch of kids on a trip find a giant robot in a cave, and are told to use it to protect the world. It gets very very dark.
• Life Lessons with Uramichi-Oniisan takes place on the set of Together With Maman, a parody of the long-running Japanese children's show Okaasan to Issho. With all of the antics that happen on the set due to how dysfunctional the actors are, you'd think Together with Maman would be an In-Universe example, but it's actually a subversion. From all outward appearances it's a perfectly normal kids' program, and at least one chapter shows that they cut particularly ill-fitting shots out of filming.
• Several episodes of Pop Team Epic have segments featuring puppets of Popuko and Pipimi that start out innocently, but get dark halfway through. One segment, "Go To Sleep, Kon-Chan!" begins with the girls singing a cute song about putting a baby fox to sleep, but then Popuko yells at the viewers that they should be asleep like the baby fox in the song. The most well-known example, "The Heart Tree", starts out as a song about growing up, but when Pipimi starts clapping her hands to the melody, it turns into a song about how destroying things can be fun.
• Popotan: Staples of saccharine cutesiness that one would normally expect from Nick Jr., including the music, art style, and various antics... that involve lots of sexual innuendoes. It also zigzags with melancholy seriousness, especially towards the end.
• Puella Magi Madoka Magica starts out your standard cutesy Magical Girl fare. Then Episode 3 delivers its Cerebus Syndrome/Deconstruction double-whammy.
  • The Rebellion Story: Homura's Soul Gem world is also one of these. It indeed appears to be cutesy Magical Girl fare, taking all sorts of cues from Lighter and Softer fanart and fanfiction depictions of the series. Then Homura discovers that the world is actually a witch barrier...
• Shadow Star: Playful tomboy finds a cute little star-shaped creature with superpowers and develops a bond with it. Tragedy ensues when she encounters similar monsters bonded with other children who aren't so nice.
• Sword Art Online has an episode, "Red-Nosed Reindeer", that sounds like it would be a sweet Christmas special. It's actually a tragedy. All of Kirito's friends die in front of him because of his mistake, and then he devotes a bunch of time and effort toward a rumor about a magical artifact that he could use to resurrect his girlfriend, only to find out he's six months too late. Then he receives a surprisingly cheerful message that she wrote before she died, telling him not to beat himself up too much because she had accepted long ago that it was only a matter of time before she met a violent end. Merry Christmas!
• Yuki Yuna is a Hero looks like a fluffy Magical Girl Warrior anime about friendship. Aside from some minor fanservice, all is fine until the hints that all is not right start popping up. By the scene where Togo attempts suicide in front of her friends, fails, and casually mentions she's tried that several times it's obvious that the anime isn't for little girls.

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