Okay, so there's a pretty significant difference between books 1 and 2. Unfortunately, they were not quite on the same page.
Book 1: the lead-up to the big reveal. I love the reference to the title in that Ladybug and Chat Noir literally keep meeting up back-to-back so as to not reveal their identities but to continue hanging out together. Chat Blanc setting off Adrien thinking about the present from Ladybug and putting the pieces together is BRILLIANT. It was kind of funny how intense Adrien was about tracking her down, and sweet how he still refused to break her trust during their back-to-back hangouts. It was pretty fun watching his little lovestruck investigation happen. All the dreams with Chat Blanc and slowly piecing things together were also interesting. It shows us that a part of Adrien subconsciously knew all along that Marinette was Ladybug. One thing I'll say, though: huge revelations, but not big enough reactions. All these big reveals happen, but the characters do not give us enough satisfaction. And most of the reason I'm reading this is waiting for the Big Reveals.
Book 2: did not need to happen. This is basically just a Felix-centered story about his obsession with Marinette. There were some suprising twists with Evil Emilie and Felix's desperate lovelorn-ness (I kind of enjoyed it at first, despite absolutely loving his canon and very surprising relationship with Kagami), but I was mostly just bored and cringing at the terrible OOC. Adrien is so overprotective that it's lowkey gross, and he gets so aggressive towards Felix. It felt so off. Not to mention, Marinette Dupain-Cheng is a badass and Adrien knows it, but he was constantly treating her with kid gloves and handling her like some delicate china. Also--and this made me so uncomfortable--he and Marinette are ALWAYS KISSING. Like, in front of EVERYONE. ALL THE TIME. It was horrific, truly. And it gets worse because, at several points, Adrien states that he kisses her immediately to stake his claim. The brawl between Adrien and Felix was lowkey fun because I love idiot boys abusing god-given powers to duke it out over a girl, but...no. Adrien is the goodest good boy ever. He would never. Sadly, I dropped this after Chapter 15. I just couldn't anymore.