If she discovers some of Snape's old potions recipes or magical knowledge, she could share it with the Hogwarts faculty and students. This would not only improve the potions classes but also make her a respected figure in the school. And her presence might also make the students re - evaluate their views on Snape, which would in turn change the overall atmosphere at Hogwarts.
It could be a random witch that Snape had a brief encounter with. Maybe she was someone he met during his time as a Death Eater or while he was spying for Dumbledore. She could have been a fellow Hogwarts student from his youth that he had a secret relationship with.
The plot could revolve around her search for her father's legacy. Since Snape had a complex life, she might find out about his double - agent role in the wizarding war. She may also have to deal with the fact that not everyone in the wizarding world will be accepting of her due to Snape's controversial past. This could lead to her having to prove herself and make her own mark in the wizarding world.
Another plot could be that Snape's daughter is enrolled at Hogwarts without anyone knowing her true identity. She has to navigate the school while hiding her relation to Snape. She might be sorted into Slytherin like her father and face challenges and prejudices from students who still view Snape as a dark figure. But as time passes, she shows them that she is her own person with her own values, while also honoring her father's memory.
A potential plot could be that Draco is tasked with finding Snape's secret daughter for some unknown reason. When he does, he's surprised by her resemblance to Snape in terms of her intelligence and determination. They begin to work together to solve a mystery related to Snape's past, which gradually builds a bond between them.
One possibility could be that Snape's secret daughter, let's call her Lily (for the sake of this story), has been hidden away all her life. Draco, being from a prominent pure - blood family, initially has doubts about her. But as they interact more, he realizes she has a kind heart and a sharp mind, much like her father. They might end up forming an unlikely friendship, which then develops into something more as they face the challenges of the wizarding world together, such as dealing with the remnants of Voldemort's followers.
Well, it could be about the daughter of Snape secretly having feelings for Draco Malfoy. Maybe she's been in the shadows all this time, and when she meets Draco, there's an instant attraction. Their relationship might develop against the backdrop of the wizarding world's politics and power struggles.
Dumbledore could be an important character too. He might be aware of Snape's daughter's existence and see the potential in her relationship with Draco. He could be the one guiding them, or at least observing from afar, making sure their relationship doesn't cause any major disruptions in the wizarding world.
One idea could be that the daughter inherits Hermione's intelligence and Snape's love for potions. She could be a brilliant young witch who is constantly trying to bridge the gap between her mother's Gryffindor friends and her father's Slytherin past. Maybe she uses her skills to create new potions that help solve magical mysteries in the wizarding world.