I've never written a review on this site before, so this will be my first and probably only dive into it, solely because no review does this manga justice and it seems like everyone has completely misjudged the direction of what Ijiranaide, Nagatoro-san achieves.

Initially Nagatoro-san plays itself off as a shallow, one track idea and nothing else. It takes the notion of teasing and bullying on topic of the cliche that is our very common anime/manga trope at this point; the nerd/otaku.

Opening into it I was mostly reading along further because the art is quite clean and there were not all that many chapters out at the time of writing this, however, by day 2 of reading my perspective began to shift on how this manga actually portrays what is behind the jests and shenanigans and the art has a massive role to play.
Most of those writing reviews are to comment on how both the main characters look fantastic and I don't discredit that but the main factor of the art being such a driving force is because of the nuance. With the very detailed facial expressions we get we are delivered a multi-tone perspective in a single panel which is very rarely replicated by other visual stories these days. Certain moments keep the hyper-expressiveness within certain margins that tell you the story behind and about the choices of the characters actions.
Within 30 chapters we see 'Senpai' grow confident in the environment that has been fostered around him and even see him longing for it contrary to how he says he is feeling about his relationship with the girls. Most notably at the festival.
More importantly however is how Nagatoro is portrayed through her demonization, her actions may be a level of harassment and they are fully intended to be and anyone with a simple level of understanding can see that she is incredibly interested in Senpai, this is made apparent by her completely dis-infatuation with other men but she is also using Senpai as her only outlet to not be the person she enjoys the company of.
Nagatoro is an equally self-embarrassed person with very few comfort-zone people in her life. Senpai is one of the few people that she has found beneath her and whilst definitely has notions of revelry when it comes to being a tormentress she is also acting in ways she finds completely embarrassing to cover for how she feels. What makes this interesting is that she has learnt the boundaries of Senpai and he takes on the emotional load of the scenario because he doesn't read deeper into her when its directly affecting him, leaving Nagatoro to keep reign and a personal comfort in that which is an unspoken mutuality in their likenesses.
Almost all told exclusively within the facial expressions.

Nagatoro as a result tells us the tale of the feelings that are within a person that lashes out as a bully but not sympathetically from the bullies point of view, we are given very narrow space to empathise with the bully from the view point of the one BEING bullied. Leaving most with the standard feelings they would as if they were being bullied themselves, its not a pleasant feeling and bullies will never try and leave an emotional opening, especially to someone they consider weaker than them as it is the direct impact to them falling down a far deeper pit than that which they are in. As a reader we have a beautiful balance on this spectrum which lets us fold back the blinds just a little bit every so often to glean how Nagatoro feels without being invasive or particularly short lived, and I say this on a level very different to that of the fundamental relationship story it has going on.

Sure on some levels you can tread on this manga as a piece of fetish catering fan-service but through the thoroughly blurred lines the manga eludes its meaning just as much to the cursory reader as it does our main character. I would even go out on a limb and say there is no standard sexualised content in this manga for what is widely thrown into the Japanese art net. Most of the situations with any small clothing content have been used as a tool to propel the ideologies hiding within plain sight and with knowledge of this the author has not once delved hard into those visuals more than the original portrait shot and at other times is used as quite legitimate sexual harassment more than anything else.

Overall I for one was astounded to find such a change of pace and seriously enjoyed reading this with all minor detours it takes off the trail to look at the flowers, flowers with very prominent sharp thorns but those with the insight to smell before pulling might find something more to it.