Being a passerby in HP female protagonist fanfiction

As the title suggests, I'm a bright and innocent college student who accidentally transmigrated into a Harry Potter fanfiction featuring a strong female lead, becoming a minor character. Facing a winking owl, I fell into deep thought. Ah... Sorry, main characters, I firmly choose the slice-of-life genre. Please don't question me. Reading Reminders: 1. The main storyline is the female lead's daily life at Hogwarts, with slight mystery-solving and dark elements. 2. All-female romance, slow-burn type, very subtle yet profound romance, and includes both male and female characters! No BL fans allowed! 3. There are many original characters, but their roles are small in the early stages. 3. The female lead will not have any romantic relationships with anyone...