Their conversation in the bath is about twice as long in the book, a lot of minor things and gags were cut, but nothing that really changes the general understanding of it to be worth mentioning.
Koyomi's hair as well is something that flows much smoother in the novels as he mentions it's length and how he is letting it grow in at least half of the books, while in the anime you can barely see any difference until it's suddenly long in Hana. I'm not sure if the anime even said it at any point, but he is growing it out so it covers the bite marks Kiss-Shot left on his neck.
Not much lorewise to talk about otherwise, but there are a couple of nice easter eggs in this episode!
When he was left alone with Tsukihi at the start, the choreography he was dancing was Platinum Disco, Tsukihi's opening from Nisemonogatari!
Also, when he asks about the disbanding party with a bunch of middle school girls, the silhouettes are the girls from Madoka Magica, another of Shaft's series (and a very good one at that).
It's so very Monogatari to start a new arc and make the first episode have nothing to do with the title character xD
![Judgment Commentary! | Tsukimonogatari | Episode 1 "Yotsugi Doll, Part 1" [Reaction + Discussion]](https://img5.samukata.com/storage/10/ss/hr/4e9b88-019e8309-5d5a-716c-a599-632734baf689.jpg)
