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: Monica's Gang
Base Breaker: Monica and Jim as a couple, since Manga#34. There are those who still want them to be together and those who think they don't work as a couple anymore because of their own personal matters that interfere with the relationship, and thus causing many to Abandon Ship. However, whichever side it is, everyone agrees on one thing: Monica and Jim's romantic subplot became a Romantic Plot Tumor, coupled with Relationship Writing Fumble, because they become absurdly obnoxious because of the Belligerent Sexual Tension between them.
Jim himself. Sometimes he is justified in some of his actions, such as being angry at Monica acting moody for the remainder of their date at one point simple because Jim glanced at other girl (proven further by Maggy) or her ever irritating hatred of Irene, but sometimes, the "Jerk" in his Jerk with a Heart of Gold can be way past tolerance. Needless do say, this can be quite a divider among readers.
Big Lipped Alligator Moment: At one point in the first movie, when Franklin is about to explain his invention, a duck randomly flies in and starts dancing, quickly getting shooed out by Franklin. Twice, even. The third time Franklin tries to explain his invention, a worm comes out of a fruit and performs a magic trick, only to leave after getting stared at by Jimmy Five and Franklin.
Cliché Storm: The initial arc, covering the first four issues of the manga series, stacked every single manga cliché you can think of. Because of this, So Okay, It's Average art (especially considering how the characters are looking now) and bad writing, this arc is edging ever closer to Canon Discontinuity.
Designated Hero: Marina got hit with this hard in one particular comic. Said comic's plot involved her doing drawings of Smudge bathing, a nude drawing, mind you, and freely handing out copies of them to everyone in the block, and when Smudge got understandably offended by it and Marina countered with "It's just a drawing" and brought up the Freedom of Expression issue and Smudge stole her art instruments as revenge, Marina then proceeded to fill the walls of the streets with the very same drawing as payback. So Marina got away with not only violating policies of consent regarding Smudge, but also got away scot-free with vandalizing public property, and the story treated her as being in the right and Smudge in the wrong.
Manga!Nick Nope is so popular that he got a entire arc involving him as a protagonist. The arc's plot also involved an Iron Man parody movie (complete with a Robert Downey Jr.-inspired character!) everyone except Nick was obssessed with.
Jerkass Has a Point: Captain Fray in the manga manipulated everyone into thinking he's a good guy as Kid Clean and that Smudge, who had his powers at the time, was a bad guy despite trying his hardest to make good use of his powers so Smudge would give up his powers allowing Fray to regain them, meaning he had a chance to start clean but ignored it. He also had an excellent point in how easily Monica, Jim and Maggy turned against Smudge to the point of avoiding him and keeping him in the dark because of the nature of his powers alone.
Harsher in Hindsight: After the Teen Gang issue #34 where Jim reveals that he feels absolutely worthless in comparison to Monica and that becoming Monica's equal is the reason he tries so hard to do achieve a position of superiority, every instance in the manga where Jim's plans to achieve superiority and his friends put him down or make fun of him, or do things to strike down his ego before and after issue #34 becomes this.
Mary Sue: Marina was accused of being one. Later, accusing her of being "too perfect" became a Berserk Button for her.
Monica in the manga, going between Mary Sue and Jerk Sue, depending of the story. To elaborate, she can act as bitchy as moody as she wants towards her friends, she has an Irrational Hate for Irene just because she thinks Irene is a threat for her, she won't accept people disagreeing with her, and yet she has lots of boys fawning over her, she always gets her way, is Easily Forgiven within a matter of seconds, if she's called out on her attitude she dismisses it instantly, and when she acknowledges her flaws, the writers seem to hit the Reset Button and she goes back to square one.
The whole Bug-a-Booo (Penadinho) branch. It takes place in a graveyard, and the characters are ghosts and monsters, but given Mauricio's art style...
Lampshaded in one comic when they were forced to adapt a scarier style. However, by the end of the story they switch to a cuter, babyish style because the scary one was creeping out children.
In another story, they find a Flat Earth Atheist that refuses to believe them to be real (a parody of a famous Brazilian skeptic named Padre Quevedo). In the end of the story, they confront him and demand to know why he doesn't believe in them. He answers that he's Dead All Along and always wished to turn into a ghost, but after he died, he turned into a zombie, scary enough to make them freak out and run away.
Junior is the character that's the closest to being one. He went from being a generally nice Picky Eater kid to a Bratty Half-Pint that rarely gets any negative feedback from his actions and 90% of the time he shows up, he's going to be annoying other characters (mostly Jimmy).
Manga,anime, sci-fi and sentai fans also are not pleased with his grown-up self since he basically said that grown up people aren't allowed to like all things anime,sentai and sci-fi and began to constantly annoy Smudge about it.
From Chuck Billy'n' Folks, there's Genesinho, The Rival to Chuck for Rosie Lee's affections.
Unfortunate Implications: Manga Issue #54, which centered on an Attention Whore trying to hog all of the boys' attentions with no respect of whether they had girlfriends or not, had Maurício's post-story notes talking about girls like her being a danger to relationships. While the note in itself delivered the message excellently, not at a single moment the male side of the fault was brought up, which was constantly shown in-story with how easily the boys are swayed by the Attention Whore and quick to ditch the other girls.
Maggy and Todd's Relationship: It's perfectly fine to admire someone else while on a relationship. It's also perfectly fine to berate your boyfriend if he looks at someone else the same way you look at the Hot Teacher you have a crush on. And hey, even if your boyfriend says he trusts you, by all means, it's absolutely fine to stalk the Hot Teacher without thinking of what would be of your boyfriend if you were found out, to be angry at your best friend if she points out that this crush is getting past the limits and to swoon over the Hot Teacher in front of your boyfriend. It's not like it's going to hurt his feelings or anything like that, because hey, even though you show more feelings directed to the Hot Teacher than to your actual boyfriend, what you feel for the teacher is nothing but a crush and your feelings for your boyfriend are much deeper.
Jim and Monica's...thing: If the guy you like needs to defeat you so he can feel worthy of being with you, instead of being a supportive, loving, nice boyfriend, wait for him no matter how long it takes, because it's worth it, despite you two doing nothing but argue all the time and you not making any improvement whatsoever out of it and hurting those around you over it, even though the nicer, understanding guy who doesn't care about any of that stuff and is into you and you alone is right there for you.
From the "Shadows of the Past" arc: If the guy you has a crush on has been cutting off contact with you to protect you because he's being blackmailed by the Big Bad to date her otherwise she'd show the police footage framing you for property invasion, because you both know that if you knew the truth you'd want to break into the Big Bad's mansion recklessly, throwing a Spanner in the Works on the plan he put together to get you out of this pickle, you're in the right to be mad at him for lying to you despite having a good reason to, which you acknowledged, and to act absurdly hurt and vulnerable by it and go on over how you can't stand blows like this anymore and how much pressure is put on you two getting together, despite the fact that there was a lot at stake in regards to you but hey, none of this matters because he wasn't honest to you. Nevermind that you'd probably not be able to get anywhere in life if you had a footage like that on your record. Feelings are all that matter.