These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Lupin III
Alternate Character Interpretation: Manga!Lupin not only regularly scores with Fujiko but is an outright rapist whose capers can be anywhere in the moral alignment and committed for any reason; Anime!Lupin is an unsuccessful Handsome Lech whose crimes tend to be either harmless or against Asshole Victims; and Cagliostro!Lupin a Chivalrous Pervert securely on the side of good.
Big Lipped Alligator Moment: The opening motorcycle chase sequence from The Legend of the Gold of Babylon gets a big "WTF" from a lot of first-time viewers.
Pretty much all of Legend of the Gold of Babylon gets a big "WTF" from a lot of first-time viewers.
Bizarro Episode: The second series was especially prone to these. Having to release a new episode every week for three years meant they couldn't all be winners. Such as the one where Lupin wants to steal a cat who eats nothing but pencil shavings. Or the one where he decides to go to the moon using a popcorn-powered rocket. Or the one where he steals a diaper so an old lady can write a newspaper article. No, these are not the results of some random generator somewhere.
Die for Our Ship: Fujiko suffers this at the hands of fangirls sometimes.
Estrogen Brigade / Periphery Demographic: Despite the series clearly being a seinen, the sometimes unintentional Ho Yay moments between the lead males in the anime entries manage to attract a growing female fanbase.
Fanon Discontinuity: Both the producers and some of the fans would like to ignore the pink-jacket era (consisting of the third anime series and Legend of the Gold of Babylon) altogether.
Les Yay: It isa seinen, after all. A fairly light amount but it is there such as in the Columbus Files where Fujiko woke up in a bed belonging to a young woman by the name of Rosaria. After Rosaria explained to Fujiko about that Rosaria brought her here after she found Fujiko's unconscious body nearby but jokingly reassured her that "she didn't do anything to her". The episodes where they contain cults of scantly clad curvy women can occasionally give that vibe as well. Expecially when one of them try to seduce Fujiko... only to punch her in the stomach very hard when she refuse and point a gun at her.
The Cliff Hanger laserdisc game, made using footage from The Castle of Cagliostro and Mystery of Mamo.
The Carl Macek dub of Castle of Cagliostro contains one of Macek's most infamously cheesy "translations": when Goemon slices off Lupin's burning clothing, "Once again I've cut a worthless object" becomes
Also, from Episode 0: First Contact, Zenigata tries to order a HAMBAAEEEGAAAHHHH!
Lupin's jacket comes in three different colors; fans actually refer to series and movies by which color he's wearing.
The red jacket in particular is the most recognized and often the most referenced, often serving as a sort of shorthand Shout Out to the series itself.
Having been in the hands of so many directors and writers throughout its 40+ year history, any real continuity between the films, TV episodes, and TV specials is pretty much nil, other than the most basic aspects of the characters and plot.
Even the original manga has this issue; Monkey Punch was known to set up stories in one chapter, only for him to abandon them completely by the next one, with not even a reference in the new story to what had happened before. Hell, his original plan was to have "Fujiko Mine" be the name of every woman in the series. This resulted in Fujiko having no fewer than four origin stories within the first few volumes. Monkey Punch eventually got just as confused as everyone else and decided to just make Fujiko a single character.
Nightmare Fuel: In Goodbye Lady Liberty, the scene where Fujiko is forced into a possession ritual by the Three Masons sect might make your skin crawl.
In another episode, Lupin has an encounter with Mephistopheles. Who then brags about having the former's heart in his hand. And then squeezes it, making Lupin writhe in pain on the floor, while surrounded by creepy marionettes laughing at him in unison. It's soon revealed to be All Just ANightmare Sequence, but still.
What an Idiot: Lupin meets with Fujiko after a betrayal coming out of her and what does he do about it? Continue to blindly trust her, instead of just simply dump her. This is gonna happen every single time.