One possible plotline could be that Barry Crouch Jr., while undercover or having a moment of redemption, saves Harry from a dangerous situation like a Death Eater attack. After that, they start to interact more, and a romantic spark begins to form as they realize they have more in common than they thought.
There are not many well - known specific 'barrty crouch jr saves harry' romance fan fictions off - hand. However, you can try searching on major fan fiction platforms like Archive of Our Own or FanFiction.net. Just type in the keywords 'barrty crouch jr saves harry' and then filter the results for romance. There might be some hidden gems waiting to be discovered.
In a more complex plot, Barty Crouch Jr might be in the middle of a spell that could harm a lot of people. Harry, seeing no other way to stop him, stabs him. But this action might have unforeseen magical consequences, like a dark energy being released that starts to corrupt the Hogwarts grounds. Harry would then have to find a way to reverse the damage while also dealing with the fact that he has killed someone.
The idea of Barty Crouch Jr saving Harry and a romance developing is quite interesting. Barty Crouch Jr, who was involved in so many dark deeds, could be given a new path in this fanfiction. When he saves Harry, it's like a new beginning for both of them. Harry, being the hero we know, might be initially shocked but then drawn to Barty. The romance could be a slow - burn one. They might start as friends, with Barty protecting Harry from other threats that lurk in the wizarding world. As time passes, their bond deepens into love, and they have to face the challenges of their different backgrounds and the reactions of the wizarding community.
The relationship could start with hostility. Harry, knowing all the bad things Crouch Jr. has done, is full of hatred. But as the story progresses, he could learn about Crouch Jr.'s tragic backstory, which might make him more empathetic.
It could be that a powerful sorcerer in the Avengers' world goes rogue and starts using dark magic. The Avengers don't know how to handle magic, so Harry is called in. He has to face this rogue sorcerer, using his own brand of light magic. Along the way, he might have some clashes with the Avengers' way of doing things, but in the end, they all work together and Harry manages to save the day by defeating the rogue sorcerer and restoring peace in the Avengers' world.
A plotline could involve Petunia having a change of heart due to a magical event. For instance, she might accidentally stumble upon some of Harry's magic or receive a message from the wizarding world about his importance. This could lead her to stand up against Vernon and protect Harry. She could then start to teach Harry about his mother's side of the family and the magic that runs in his veins in a more positive way than the Dursleys ever did. And perhaps she even helps him develop his magic skills secretly before he goes to Hogwarts.
In some fanfictions, Bellatrix might save Harry because she is magically bound to him in some way. Maybe a spell backfired and now she has to protect him. Or perhaps she has a secret love for Sirius Black (Harry's godfather) and in order to honor his memory, she saves Harry. There could also be a plotline where Bellatrix is tired of Voldemort's tyranny and sees Harry as the one who can overthrow him, so she saves him for the greater good of the wizarding community.
One possible plotline is that Harry is magically transported to the Naruto world and discovers Naruto is in danger from a new, powerful enemy. Harry then uses his magic to fight alongside Naruto and his friends, saving Naruto in the process.
One possible plotline could be that Voldemort discovers Harry's abuse through his Death Eaters' spying. He decides to save Harry as he wants to turn Harry to his side and believes that by rescuing him, Harry will be more likely to join him. Another could be that Voldemort has a moment of self - reflection and realizes that the way Harry is being treated is wrong, so he steps in.
One possible plotline could be that Amelia Bones discovers a plot against Harry before it's too late. Maybe she uncovers some dark wizard's plan to harm Harry at Hogwarts and uses her position in the Ministry of Magic to protect him. For example, she could assign extra guards to the school or personally investigate any threats.