I love magical girls, so I'm going to keep reading it. But for now I have only read the first chapter, and I don't know if you explored more or it isn't a problem anymore. So based only on the first chapter.
It needs more built up, I couldn't empathize with the MC because I haven't been in a similar situation. You could think of "show don't tell" that advice applies to the MC, there's no evidence to prove she(?) wouldn't be accepted by her parents or the girl, she said they wouldn't, the parents said they don't accept LGBT. Everything was said, and I didn't believe it; I have no reason to think it was a good choice to become the daughter of the teacher and leave her family.
Your dialogue was a bit stiff too, and kind of rushed. Giving me no clue about the characters personalities.
Imagine if instead of the news saying "someone" beat that person in the bar, it was treated as just a fight and the father reveals it was him who fought, and the person belonged to the LGBT community, and the mother congratulating him. Then you showed us the fear the MC feels if she ever reveals the truth. And showing a memory of the crush talking shit about trans people, or just some mean comments that are unintentional. Then accepting the teacher offer would made more sense, and we the readers would support that choice.
Also the teacher should have seen or know the father's ideology, or talk more with the MC and fully understand the circumstances; it would made a lot of difference and the perception would switch from "She's helping herself and using the MC" to "She's helping the MC and is someone who we can trust."
I hope this helps