Many in the wizarding world would be very suspicious of her. Her friends might even be divided. Some might try to understand her reasons, but others would be quick to condemn her actions. It could cause a great rift in the community she was once so respected in. For example, the Ministry of Magic might start to view her as a threat and keep a closer eye on her activities.
The wizarding world would likely be shocked. Hermione has always been seen as a defender of the light and the rules. Helping a Death Eater would make many people question her motives and loyalty. Some might think she has turned to the dark side.
It could also be that Hermione is on a mission to gather information. By helping the Death Eater, she hopes to gain insider knowledge about the Death Eater's group or their plans. This would be a strategic move on her part, using the situation to her advantage in the fight against the dark forces.
It could make her more empathetic towards the idea that not all Death Eaters might be completely evil. The fanfiction might show some grey areas in their characters.
One possible fanfiction could be where the Death Eater is secretly an undercover agent for the Order. He helps Hermione by providing crucial information about Voldemort's plans. This could add a whole new layer of intrigue to the story as Hermione has to decide whether to trust this unexpected ally.
Some in the wizarding world might see it as a chance for redemption for the Death Eater. If Hermione can reform him, it could be seen as a positive thing. But most would still be very cautious and watchful, fearing that it's all a ruse by the Death Eaters to cause more chaos.
Hermione would use her vast knowledge of magic. For example, she could use concealment charms to hide the Death Eater from other Death Eaters who might be looking for him. Also, she might use polyjuice potion to disguise him if they need to move around in public.
She might react with caution at first. Given that Death Eaters are known for their cruelty, Hermione would be smart to be on her guard. She would likely start by gathering information about the escaped Death Eater, like his known abilities and any possible weaknesses.
Well, it could be that Draco is forced to follow the Death Eater path while Hermione is fighting against them. But then, they might get thrown into some situations together, like being trapped in a place. Draco realizes that Hermione is not just a Mudblood in the sense that he was taught, and they start to form an unlikely bond. Their relationship could be full of tension, with Hermione constantly trying to convert Draco or at least make him see the wrong in what he's doing, and Draco struggling between his loyalty to his family's Death Eater ideals and his growing feelings for Hermione.
Bellatrix Lestrange is also a likely candidate. Her encounter with Hermione would be extremely intense. Given her loyalty to Voldemort and her rather unhinged nature, she would likely pose a serious threat to Hermione, but Hermione might also find a way to use Bellatrix's madness against her.
In some fanfictions, Hermione as a Death Eater is a very interesting and often controversial portrayal. Sometimes, it might show her being forced into the role due to some dark magic or blackmail. This completely flips her good - girl image from the original series and allows for a very different exploration of her character.
In this type of fanfiction, the relationship between Hermione and the Death Eater could be very complex. Maybe it starts as a hostile one, but as the story progresses, they might find some common ground or mutual understanding. It could also be a story of redemption for the Death Eater through Hermione's influence.