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.
Esdese; she's either a Badass who acts as a worthy adversary against Night Raid, or she is a broken Villain Sue who is just too boring, and predictable, to watch as you're always expecting her to just effortlessly win her fights.
Kurome started off as mostly a boring character no one was really interested in aside from being Akame's crazy sister. However, she ends up garnering a lot of hate for what she did to Chelsea's corpse after killing her off. Afterwards, she starts showing a much more loving side to her through major Ship Tease with Wave, but some fans just can't bring themselves to forgive her. Showing off her Yandere qualities after turning Ran (who was on the verge of death) into another one of her clone fighters hasn't won her any favors either.
Some fans are pointing out that they're tired of the constant displays of the corruption of the Empire, claiming that it's done for "shock value" in the same way a Snuff Film does.
An ongoing debate regarding the overall manga is, whether or not, Takahiro is making the right choice regarding how he writes Akame ga Kirus character deaths. On one side, you have those who love the fact that Takahiro actually has the balls to kill off his established characters; keeping the readers invested as to who lives and who dies. On the other side...you have those who could care less about who is about to kick the bucket, because these characters die off so suddenly that they never receive any proper Character Development to truly hit the reader where it hurts.
Draco in Leather Pants: Esdeath is a brutal, sadistic Social Darwinist who simply has no comprehension or empathy towards weaklings. However, because of her lovable moments with Tatsumi and some of Pet the Dog moments there are still fans who feel she can be redeemed. Or see her simply a product of her environment.
Name any Night Raid member not named Tatsumi or Akame, and you'll find that they all have some form of a fanbase. Mein however, became the front-runner amongst the Night Raid darkhorses (most likely due to her Tsundere stereotype); especially in the later chapters where she officially became Tatsumi's girlfriend.
Wave and Bors stand out as the most likeable members of the Jaegers, despite their actions. Ran qualifies as well after finally getting some screen-time to build his character in chapters 47 and 48; proving to also be a rather likable Jaeger member who many have jokingly nicknamed as the "Suzaku" of Akame Ga Kiru due to his desire to change the empire's system from within.
While Mein already had a lot of fans, supporters of the Tatsumi/Mein ship exploded in number after Mein's battle against Seryuu, where Tatsumi rescues Mein from Seryuu's Taking You with Me attack. And then they became an Official Couple in chapter 45.
Tatsumi/Esdese holds a strong following amongst those who still hold out hope that at some point down the line, Tatsumi will reform her.
There is also Wave/Kurome, although fans see it unlikely due to the several deathflags.
Holy Shit Quotient: When you're first reading through chapter 1, it starts off looking like a fun, innocent, adventure following Tatsumi's escapades around the capital city and landing a job as the bodyguard for a cute rich-girl. After that...
Memetic Mutation: Prepare to see forums involving the word "deathflag" due to the large amount of major characters dying.
A translation of the title: Akame Kills!
The imageboards noted how Akame in the anime adaptation kinda physically resembles Shino, especially when making chibi faces, and just ran with it.
Moral Event Horizon: Due to the dark nature of this manga, there are sure to be many, be it major-characters, side-characters, or even background-characters, that have crossed this point. The more famous examples being:
The woman who shelters Tatsumi in the first chapter; being discovered to have tortured to death the people she brings to her home; including the two friends Tatsumi was travelling with prior to the start of chapter 1.
Seryuu's brutal murdering of Schere.
Team Wild Hunt raping and killing Bors' wife and child on his grave.
Narm: In the first episode, Akame slits a guard's throat. The guard then proceeds to explain to the audience that this is 'a fitting fate for one such as me... whose true nature is rotten' (not in an internal monologue, mind you - he actually says this while there's a dirty great hole in his windpipe) before slumping over, dead. It's exactly as silly as it sounds.
Nightmare Fuel: Oh boy where do we begin? The tortured people from chapter 1?
No character (at least before team Wild Hunt's introduction) receives more hatred amongst the fandom then Seryuu due to her psychotic sense of "justice" and for having practically no redeeming qualities to her character outside of looking cute when she's not in her insane nut-job persona, and being the cause of Schere's brutal death certainly won her a lot of hate. No one felt an ounce of remorse for her when she kicked the bucket in chapter 38. In fact, its one of the most loved chapters of the manga!
Shura and his team Wild Hunt members shot up to this status instantly the moment viewers had to read through their brutal murders of Bors' wife and child in chapter 46.
Villain Sue: Esdese. Never mind being the most powerful fighter in the setting, she most exemplifies this trope effortlessly beating half of Night Raid and then freeze frigging time to stop Susanoo from killing Night Raid's target. No repercussions, nor anyone capable of beating her are in sight as of Chapter 42.
Boss even says herself that they would need an entire army just to take on Esdese by herself, and even then it's not a sure thing.