I hope I can find something more interesting to latch onto with Noriko when I replay her stuff, but on my first playthrough I really wasn't a fan of her as a character. In a game full of well-written, multi-faceted characters, she comes across as one-dimensional in a way that gets awfully close to "porn logic".
Pretty much her entire identity seems to be defined around completely unconditional love for Sensei. Somehow this love grew despite not seeing him for years, and the last time she did know him she was still a preteen and he was probably emotionally closed off after the accident. It's also hard to understand how any good qualities she saw in him could outweigh the fact that she knew (or at least heavily suspected) that he groomed/molested wizard Maya.
She again gets confronted with what an awful person he is when Ami cucks her, but her only response is to get sad and avoid Sensei for a little while. After that it's right back to unconditional love and pretending nothing happened, with no indication that she's been changed by learning that Sensei has a sexual relationship with the niece/daughter that he's raised since she was a child. We know the relationship only started post-resets, but Noriko has every reason to assume that Sensei groomed/molested Ami as well. And while she does bring that up in the immediate aftermath, it seems like she's mostly only upset that there is one more girl that Sensei loves more than her.
I feel like Noriko needs to experience some sort of rude awakening if she's ever going to exhibit any character growth, but I have no idea what could get through to her when the shit she's already seen hasn't.
Are we actually sure that she couldn't find him?
Maybe I'm reading too much into something just meant as an easter egg, but it's awfully convenient that (in Chapter 1) she's standing right outside of the cafe when Sensei walks in and is still there when he leaves. And while I can't remember exactly what details we've learned about her pact with Maya, isn't she not supposed to be in this part of town at all? I have to imagine she would only break that for Sensei-related reasons.