There is such a thing as filler even when it is in the original source. This is when characters are introduced with no foreshadowing, somehow tangentially interact with the main characters, and just as promptly disappear, usually after their own individual problems have been solved, leaving no lasting impact on our protagonists, and reverting the situation in the main character's lives back to the status quo, as though they had never existed at all.
This is clearly a cop-out by the writer, who decided to stop writing the story of the protagonist, for whom's sake we're reading the story in the first place. We want to know what happens to the main character. We want to know how the problems posed in the opening of the story are solved at the end of the story. When you just introduce some frivolous new character with their own set of problems, and then solve those problems, and then have the character disappear again, what you just did was write an entirely new story inside of the old story. And the problem is, the new story isn't remotely as good or interesting or compelling as the old story, so everyone is stuck having to read absolute junk just so that they can someday get the actual reward they've been promised, the resolution of the original story. If the new story really were better than the old story, instead of just planting it smack dab in the middle of someone else's story, it would have had the strength to stand on its own two feet, and it would have been the 'main story', the 'protagonists,' and so on. By the very fact that it's just appearing as a side story in someone else's tale, you know already that it's going to be shallow and weak compared to the original.
A large cast works great so long as the entire cast is working on the same problem together. Whether this is a world-destroying menace, or making an anime like in Shirobako, or everyone debuting as an idol group like in Idolm@ster, large casts with unified problems are all the main characters, because they're all trying to solve the original, main problem the story started with together, and when the story resolves successfully for one, it will also mean the story resolving successfully for all the others.
Even in Bakuman, the tales of the woes of the other mangaka relates to the woes of the main character's attempts at making manga. Since they collaborate with each other, get inspiration and encouragement from each other, compete with each other, and are fans of each other, it doesn't feel out of place at all to keep track of their manga careers as well as the main character's career. Like with Idolm@ster, it really feels like they're all in it together.
Maria-sama ga Miteru does tend to ramble off into side stories involving side characters, but at least they have the excuse of all being related to each other by all being in the same student council together and all being fast friends to each other. Since they constantly interact with each other on a daily basis, how their own life is doing directly relates to how Yumi is feeling too. Their continuous presence in the main narrative gives them the right to have a little side narrative to themselves as well.
But when you just start pell-mell introducing new characters to the cast who have nothing in common with the old characters and have no effect on the course of their lives, you're just pulling a fast one over your fans. Inuyasha is full of this nonsense. Ranma 1/2 also has this, but in Ranma's case it's forgivable because it's a gag comedy series so all it needs is fresh jokes to still be fun to read. It isn't exactly important, in a comedy's case, to ever 'get to the ending' or 'resolve the original problem.' Inuyasha wasn't a gag manga though, it was a serious, plot-driven story, so whenever it wasted our time by fighting monsters of the week, our time really was just plain wasted. The same is true of the endless, generally boring and awful fights in Jojo's Bizarre Adventure Stardust Crusaders. And sadly, the same is true of Aisheteruze Baby's second half.
In the first half of the show, the original problem is introduced, as well as the main characters. There's Kippei, who develops from a playboy to a responsible father and husband. There's Kokoro, who develops from a loner to someone who can open up to others. There's Yuzuyu, who develops from a miserable abandoned child to a happy adopted child. And there's Yuzuyu's mother, who develops from a worthless parent to a parent who can actually love and care for her child like she wanted to and was meant to. The story arcs that show this development are all great and top of the line. Unfortunately, Yuzuyu's mom's development isn't shown in the anime, because it ends before the manga ended. The others are covered deftly, but all of that development is essentially completed by episode 13. Everyone has learned their new roles, overcome their disabilities, and has found a path to happiness by episode 13, except for the mother. One would assume that the next episode or two should show the mother overcoming her issues and then the story ending happily ever after. Instead, the anime spends the next 13 episodes accomplishing absolutely nothing and wasting everyone's time with newly introduced characters we care nothing about and have nothing to do with the original plot.
Episode 23 of the anime, where Yuzuyu sticks up for her nursery school friend Marika, is probably the only worthwhile episode in the entire second half. The rest are about Satsuki's (himself a completely unimportant side character) love interest's self doubts, Shouta's (a classmate at nursury school who we've never heard about before up until this point) abusive mom, Miki's (a cousin of Yuzuyu's we've never heard of until now) running away from home, etc. Kokoro suddenly becoming a crybaby wimp wailing over her dead mom all day every day even though she's well into high school now and her mom died decades ago is equally ridiculous as a plot device. This late in the story, she's obviously already learned how to cope with her mother's death, and would only cry once in a blue moon if something specifically reminded her of it. Making a sad face all day every day over it is ridiculous. I much preferred the strong, self-reliant Kokoro over this worthless crybaby version that needs tending to all the time like a pointlessly redundant Yuzuyu version 2.0.
It's a shame, because the first thirteen episodes of this series are spectacular. They can make you tear up almost every episode for Yuzuyu's sake. When Yuzuyu feels better, you feel better too. And when she feels worse, you feel even worse than she does. It's an emotional roller coaster and a hell of a dramatic story where you can understand everyone's feelings and nobody is really in the wrong. That's about as good as writing can be. If the story had extended on in that vein it would have been like another PapaKiki. Instead it's stuck down here at 75th place because of the dead weight of the story's second half, and the fact that the anime did not resolve the mother's problems and bring a true end to the tale.
Rewatching the first half of Aishiteruze Baby was a delight. Rewatching the second half was a chore. I implore all story writers to stick to their original story. Do not resort to manga filler. Do not waste our time. Do not get sidetracked and proceed immediately to 'Go.' You are here to write the original main character's story, how that character solves that character's problems, and nobody else. Everything and everybody else is a waste of everyone's time.
Aishiteruze Baby's rewatching is finally complete. Next up is Chihayafuru season 2. This should go a lot more smoothly, since the story never swerves or deviates away from the main character's quest to become Karuta Queen. On the downside, though, Karuta isn't nearly as interesting a topic as child abandonment, so even if you stick closely to it that won't get you very far. >>.
Speaking of manga filler, the latest chapter of Bleach was a perfect rendition of nothing-hood. Not a single character's situation changed. Not even a single character's spacial location changed. It was such a waste of space as a chapter, that I didn't even have to update my bleach situational report permapost by a single word to take into account the 'action' of the latest chapter. It's hard to believe so little can happen when at the exact same time, there was so much action and excitement in the latest Fairy Tail and One Piece chapters, who apparently understand how to actually progress a story with the space they are given to draw with. It's chapters like these that give Bleach its bad reputation. Almost always, the criticism against Bleach is unfounded and obnoxious, but there's nothing I can say in defense of this chapter.