One popular 'Molly comforts Hermione' fanfiction might be 'A Mother's Embrace' where Molly offers Hermione solace during a difficult time at Hogwarts. It beautifully depicts Molly's motherly instincts kicking in.
People write such fanfictions because it's a way to explore different character dynamics. Molly and Hermione both have strong personalities, and seeing Molly comfort Hermione allows for a deeper exploration of their relationship, especially the mother - daughter - like bond that could potentially exist.
One possible fanfiction could be 'Bill's Solace'. In this story, Hermione uses her vast knowledge and warm heart to comfort Bill after he endures a particularly difficult encounter with the dark forces. She might bring him books on magical healing, both for physical and mental wounds, and they sit together in the Burrow's garden, Hermione softly reading passages that offer hope and strength.
One scenario could be that Hermione is feeling out of place among the Weasleys due to her Muggle - born status. Bill, being the eldest and more worldly Weasley, might comfort her by sharing his own experiences of dealing with different cultures during his work with Gringotts. He could remind her that her intelligence and magical ability are what truly matter in the wizarding world.
In some fanfictions, it's possible for the author to create a fictional relationship where Hermione is Molly's sister. However, in the original 'Harry Potter' series, there is no such relation.
Maybe in some fanfictions, the writer wants to create conflict. Molly might be written to hate Hermione because of differences in their personalities or values. For example, Molly is very family - oriented and Hermione is more focused on academic and magical achievements. Their different priorities could lead to friction in the fictional stories.
One common theme is the mother - daughter relationship. Since Hermione doesn't have a strong mother figure in her life, many fanfictions explore Molly filling that role, providing love, guidance, and support.
Perhaps in the fanfiction world, there are some misunderstandings. Molly could have accidentally said or done something that Hermione misinterpreted. Maybe Molly made a comment about Hermione's Muggle - born status in a way that Hermione took as offensive, even if it wasn't meant that way. This could easily plant the seed of hatred in Hermione's mind.
It's appealing because it shows an unlikely but interesting bond. Sirius is from an older generation and Hermione is very studious. Their interactions can be really unique. For instance, Sirius can introduce Hermione to a different way of thinking that is more in line with the old wizarding ways.
One common theme is redemption. Draco often needs to redeem himself after his actions during the war, and Hermione's comfort is a step in that process. For example, in many stories, he has to face the consequences of his family's loyalty to Voldemort, and Hermione helps him see a different path.