One possible plotline could be that the sister of Lily, initially having some sort of enmity or misunderstanding with Severus, gradually discovers his true self and falls in love. Another could be a more arranged - marriage - type situation where for some reason, they are forced to marry and then develop feelings over time.
A possible plotline could involve the lily sister being in a difficult situation, perhaps a family obligation or a need to protect someone. Severus, with his own motives and secrets, offers a solution through marriage. As they start living together, they face various challenges like dealing with the memories of Lily, the expectations of their families or friends, and slowly, they learn to love and trust each other, making their marriage a real and meaningful relationship.
In some plotlines, the lily sister might be on a quest to understand Lily's relationship with Severus better, and in the process, she gets closer to him and they end up getting married. It could also be that Severus, still having some feelings for Lily in a way, sees a part of her in the sister and is drawn to her, leading to a complex relationship and ultimately marriage.
I'm not sure of specific fanfictions on this topic. You can try searching on popular fanfiction websites like Fanfiction.net or Archive of Our Own. Just use the keywords 'lily sister marries severus' in their search bars, and you may find some interesting stories.
One possible plotline could be that Snape, in some alternate magical realm, gets a chance to meet Lily Luna Potter. He might initially be in shock, seeing the resemblance to Lily Evans. Maybe he tries to protect her from some unknown danger, using his vast knowledge of magic. He could also share some untold stories about her mother with her, creating an emotional bond between them.
The sister could have her own love story intertwined with the events of the wizarding world. She might fall in love with a Gryffindor, which would be a huge scandal in the eyes of some. This relationship could be a source of tension, not only within her family but also in the wider wizarding community. And as Severus tries to protect his sister from the dangers of the wizarding war, her relationship could add an extra layer of complexity to his already difficult situation.
There could be a plot where Snape's muteness is a secret that he tries to hide from everyone at Hogwarts. The story could be about how he manages to teach Potions and be a double agent for Dumbledore all while keeping this secret. Or perhaps a plot where his muteness is a magical experiment gone wrong, and the story is about his journey to reverse it. Along the way, he might discover new aspects of magic and his own identity that he never knew before.
Perhaps in a fanfiction, Clementine and Lily meet in a school setting that's not like a normal school. It could be a school for training people with special abilities. Clementine is new and Lily is one of the more experienced students. At first, Lily is a bit of a bully to Clementine because she's new and seems to be getting a lot of attention. But then they are paired up for a project and through that, they discover that they have a lot in common. They end up becoming friends and standing up for each other against the real bullies in the school.
In some 'Harry married Lily' fanfictions, the plot might revolve around a prophecy that was misinterpreted. Instead of Harry being related to Voldemort in the way it was originally thought, the prophecy could be related to his connection with Lily in a romantic way. This could lead to a whole new set of events where they get to know each other on a deeper level, overcome various obstacles in the wizarding society that would oppose such a relationship, and eventually get married. There could also be elements of family drama, like how James Potter would react in such a scenario, or how Harry's friends would view this relationship.
Well, perhaps there could be a plotline where Ranma is in a life - or - death situation and Happosai saves him. In gratitude, Ranma agrees to marry him, but then has second thoughts later. Or it could be that a mischievous character plays a trick on them and they end up married, and the rest of the story is about them trying to figure out how to undo it or make the best of it.
One possible plotline could be that in a post - war world, Narcissa and Harry find themselves drawn to each other through mutual understanding. Maybe Harry sees a different side of Narcissa that was hidden during the war, and they start to build a relationship from there that leads to marriage.
In some 'Harry Marries Lucius' fanfictions, it might start with a completely different wizarding world setting. For example, a world where the traditional enmities between the Gryffindors and the Slytherins are not as strong. Harry and Lucius could meet under different circumstances, like at a diplomatic event. Their relationship could then be a slow - burn one, with them having to navigate through cultural differences, power struggles within the wizarding world, and their own personal demons. This could all lead to their marriage and the subsequent development of their relationship.
A possible plotline could be that Naruto is chosen by Kami for some greater purpose related to the balance of the world. As a result, they get married. Their union then brings about a new era of peace and prosperity as Naruto uses Kami's power to end all wars. Another plotline might be that Kami falls in love with Naruto's pure heart and determination. She decides to marry him, but they first have to convince the shinobi world that their union is for the good of all.