As a person who read the mange first page through last, I'm pretty happy with this adaptation. Although this whole show would have been a lot like I mean A LOT better with a second season, from what it shows so far it gave me the same feels as the manga. Like me cringing that he rejected the other girl just for the sake of revenge. If I were to give a short paragraph about how this would have progressed and how it would be better it would go like this:
Kinda Big Manga Spoilers:
Okay so fake Masamune gets caught. Turns out that Adagaki had a huge crush on Masamune before, remember when they mentioned that a guy left him devastated and that's the reason why she hates men? Yeah, that guy was Masamune. Turns out that it wasn't Asagaki that rejected him, It was Koiwai. Koiwai dressed up to look like Adagaki to get revenge on Masamune because when they were at home Koiwai was like a best friend to her but when Masamune came in, Adagaki couldn't get her mind clear of him and only talking about him. like mentioned before, Adagaki was devastated that Masamune left for no reason. Little did she know Masamune left because what she thought was her rejected him with accompaniment with a low blow insult. She was crying and her personality changed, as time went by, she got worse and so did Koiwai's guilt. So when Koiwai said that she was helping Masamune get "revenge" it was actually her trying to get Masamune to fall in love with her again so they could be happy. She really felt guilty knowing that two people got depressed because of what she did. However, just to make matters worse, it seems like Koiwai caught feelings for Masamune while she was helping him but don't worry, she and Masamune did the realistic thing and didn't get together. So in the end Masamune and Adagaki get together.
Just saying the Manga is really good.