Being next to each other in class they get ample time to talk but Mizuho tries her best to act indifferently to him, especially around friends.
Usually the genre is terrible with consent and sex so the fact that Narumi is actually willing to back off, even if he is not happy with it, comes as a surprise, but a very pleasant one. So congrats Narumi, you may be a jerk but at least you understand that "no" means "no".
Narumi walks her to the bus stop and decides to tease her by not kissing her when she expected him to.
I think it is easy to tell this is one of the missing pieces of why Haruka thought of Mizuho, as it is clear that the act means a lot to her.
Mizuho greets a woman in the house. I am not sure who she is, Mizuho I believe calls her Nanao-san, and she looks to be preparing food. Not to mention the room that was a complete mess before is clean so perhaps she is a maid that comes by the house weekly or something. In any case she and Mizuho briefly exchanged words before Narumi comes by to take Mizuho up to his room.
While this episode focused heavily on the two main leads I think this is a needed episode to really get into the why of the relationship. That way it is out of the way and they can move on to the other side stories that they need to tie in to the greater story, which is why I think we see so many of the supporting characters in the preview.
Speaking of which going by that for the next episode we get to break away from Mizuho and Narumi a bit and get to see more of the supporting cast. So Matsumura Hokuto, Yasui Kentaro and Suzuki Airi fans rejoice, as all three are featured prominently.