It's undeniable that Nagatoro as a manga and as a character has had quite the history. For the uninitiated, Nagatoro first came to be as a webcomic back in 2011, a webcomic where her sole reason for existing was to sadistically punish, berate and bully the self-insert MC that is with her in the webcomic.
Going into the manga, I was personally morbidly curious to see what this would lead to. I was not surprised to see that the status quo hadn't changed, and didn't change for a few dozen chapters in the manga. She was still sadistic, she was still pretty damn evil, over-bearing and scary. This is why Nagatoro had quite the contentious era around the time the first season came out, since she really just was a bully.
But, as time went on and the story continued, Nagatoro as a manga really steers away from it's past, re-invents itself and comes out the other side as something totally new. Nanashi as an author knows the history this character has had, and has gone all the way to ensure that history is remembered, but the purpose is different this time around. The change in dynamic in the manga is a very day-brightening thing to see every week a chapter comes out.
The character development is palpable for a rom-com. The main character and Nagatoro both grow exponentially as people, to an extremely clear degree. The side-characters also get their fair share of time to gain visualized personalities to understand and enjoy. One of my favorites is Yoshi, one of Nagatoro's friends, an airhead that mostly nods along to what anyone says, with an ahoge that keeps growing every time she shows up.
The evolution of the art in Nagatoro is also great. Nagatoro has always had great expressions since the start, but as the story's emotions and theme changed, so did the expressions possible for the characters to do. The variety of emotions that Nanashi manages to express through the way the characters emote are very vivid and really elevates the experience as the reader.
It's incredible to think about that Nagatoro started 13 years ago as purely a sadistic bullying fetish, and today the series has become a genuine rom-com. The more you're aware of the history, the sweeter the journey will become for you if you decide to read this manga. I duly recommend it, it presents a one-of-a-kind experience when it comes to rom-com, as Nagatoro's redemption story as a character grows from just in-universe to a level of meta outside of the manga itself.