Hilarious In Hindsight / Negima! Magister Negi Magi

• In one chapter, Nodoka was attacked by a perverted bounty hunter with tentacles, who starts stripping her clothes off while ranting about "boobies". After Negi saves her in a Big Damn Heroes moment, the group later runs into the same gang of bounty hunters in a bath house. Turns out the tentacle guy is actually a hot female with a healthy appreciation for breasts. Skinship Grope ensues.
• In chapter 15, some eavesdropping caused the class to think that Negi was a prince. Roughly 200 chapters later, it turns out he is.
• In chapter 210, after everyone important has left for the magical world, several characters are joking with the twins about how the main cast was abducted by aliens. The twins panic, saying "next time we meet Asuna she won't be Asuna anymore." Turns out not long into the arc, Asuna gets kidnapped and replaced with a lookalike that has her personality and memories.
• Speaking of aliens. One of the major reveals later is that the magical world is based off Mars. This also happens to shed some light on Chao calling herself a Martian.
• When Evangeline was still Negi's opponent, during her duel with him, she captured a bunch of his other students and dolled them up as Meidos. Among her victims we have Akira Ookochi and Ako Izumi, who end as maids again much later... in the Magical World, when alongside Natsumi they sell themselves into slavery.
• In Chapter 229, when they find out that Fate's real name is Tertium, which means the third, they start to worry if there's more then one of them. Come Chapter 311, and we meet Quartum, Quintum and Sextum.
• The English dub of spinoff series Negima!? has a point where Shichimi says "Perhaps it is time to dine, nya" a paraphrase of Enma Ai's catchphrase from Hell Girl. It's even more hilarious when realizing that the joke was simply a Shout-Out in the Japanese version. In the dub it's a Shout-Out and a "same voice actor" joke, since Brina Palencia voices both characters.

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