Who exactly are we defining as Soma's harem? Erina, Megumi, Meat, and childhood friend have all shown active interest in him, Alice, Rindo, and the other Polar Star girls have at least acknowledged Soma is attractive/passive interest.
The ones with romantic feelings are the childhood friend, Meat, and Megumi, while Erina currently might be learning that she is in love with Soma but is not out right aware of it.
We can have post foodgasm emotions or scenes were comedy is in use like when the polar girls wonder if Soma would later look like his Dad but those aren't actual harem dedication since it doesn't become a goal set for those people.
Alice isn't in love with Soma that is a fact, she may joke with him but showcasing high end romantic attraction is not there.
The harem thing for me at least scuffles the characters a bit since they later do things with their character due to a love connection with Soma as well as having him as a inspiration. What I mean is that by setting a love plot point to the character then you create another bullet point for that said characters end goal that while become even less plausible when other competitors are added. It just makes the character have a loss added or a piece missing when they don't fulfill such a thing even if they did succeed with the other stuff. It makes it even more bigger since the love plot is connected to the main protagonist who by the end will likely win the main plot of the series and if done to conclusion will have a partner in the end game to relish with his/her success. Now compare this to characters that just use him as a inspiration and would lose against in in only being the top chef but not also later get a rejection in another plot device, therefore suffering a double onslaught.
In conclusion it becomes even more redundant since Erina from chapter 1 is the said love interest of the series and will 100% be with Soma because the main plot of the series wants it to be so. Making what you get is a character having extra pointless love panel time when it just delays the end result and acts like a side joke offering of the main plot.
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Basically what I am getting at is this
- Main Plot = Top Chef + Evolving like his Pop = Growth via Partner = Erina and Soma relationship
- Soma + Another love interest doesn't equate since part of the main Plot involves Erina (from the first chapter of Soma's Dad saying you got to have your significant other which later showed a panel of Erina, to the author putting plot pieces of them being some how connected with each arc)
Okay so your reading the series and you know this, then what is left
rivals, growth for other characters via improvement, and hurdles
bonds are formed, people get stronger, etc.... Sure they are side relationships from fellow classmates and adults which is fun to read but I just get bored with useless empty handed plot devices from it being a empty threat like that expulsion stuff over and over again to another thing that clashed with the main plot the what if love interest to Soma.
Hence why I like Megumi more then Meat since she has something more then the Soma love interest, while I feel Meat hit a wall, lost a ton of panel time, matured to her limit in her ambition and character growth (she may get stronger but she doesn't have a end goal of some sort other then Soma which is impossible).
I mean the Erina love interest only is acceptable since both Soma and Erina are evolving because of it since it is integrated to the main plot. So I can't just root for something that will go no where. It would be like me rooting for Soma's childhood friend coming out of nowhere and becoming the master chef of the series after Soma dies from a horrific cooking accident.
So I basically toss out the whole love thing and don't bother with it and what do I get other female characters like Alice, etc...
It's hard to say what's going on with Gintama and Nisekoi. They seem to be more cases of the mangak calling it quits and bringing the manga to a conclusion (since they seem tired/no longer have more to add to the story) cause as far as popularity goes, both are still pretty popular. Toriko seems more of a clear case of getting cut right in the middle of an arc (Area 6 being rushed into oblivion and everything that followed since) so I guess it is the one that the editorial is rushing.
It might just be that the editorial was looking into ending some manga, and Komi read the signs a year in advance and had been wrapping up ever since on his own pace, becuase he was also close to done, while Shima stumbled because he had this entire epic saga planned out and once he got the news, he started rushing.
Everything I read about Gorilla makes me think it's just him deciding to throw in the towel. He always jokes about how the final arc could start at any point when he feels like it, and here we are now.
I think they're just ending.
I choose bad examples but yeah who knows
Toriko is a outlier compared to those two since Toriko has a bunch of open ended stuff to conlcude.... I mean a but load relative to Gintama and then Nisekoi