In a fanfiction, where Draco's twin brother was hidden away, what led to this situation?

He could be resentful at first. After all, his parents have kept this big secret from him his whole life. But as he gets to know his twin, he might develop a sense of brotherly love. He may also start to question his family's values and actions in hiding his brother, which could lead to a change in his own character.

Maybe the twin brother has a special power that Draco doesn't. For example, he could be a seer like Trelawney but more accurate. His visions could show him the future of Hogwarts and the wizarding world during the dark times of Voldemort's return. He then tries to use this power to prevent bad things from happening, but Draco is suspicious of his actions and tries to stop him, thinking he's going against their family and the Dark Lord.

It could lead to all sorts of interesting plot twists. Maybe there's competition or a stronger bond between them.

At first, it could be strained. Draco, being used to being the only son in the family's eyes, might feel threatened by his twin. He could be jealous if his twin shows more magical talent or is more popular at Hogwarts. But as they grow older, they might start to understand each other better. For example, if they face a common enemy, like a bully from another house, they could come together and realize the importance of family.

Well, they could have a very complex relationship. On one hand, they might be extremely competitive, always trying to outdo each other in everything from academics to impressing their parents. Since they are in Slytherin, they could also team up and be a formidable duo, using their combined wits to get what they want in the wizarding world. Maybe they have a secret pact to protect each other no matter what.

The twin could change a lot. He might be the one who stops Draco from making some really bad decisions. For instance, if Draco was about to follow Voldemort's orders blindly, the twin could convince him otherwise. This would then change the whole course of Draco's actions and how he interacts with Harry Potter and his friends.

You can try looking on fanfiction websites like FanFiction.net or Archive of Our Own. They have a wide variety of fanfictions, and you might be able to find some with the 'led draco leash' theme by using the search bar and typing in relevant keywords.

She could be really kind. In contrast to Draco's sometimes haughty attitude, she might be the one who is always helping out the first - years, showing them around Hogwarts and making them feel welcome.

Since it's a very specific type of fanfiction, the common themes could also revolve around the uniqueness of the Draco as a pet. Maybe the stories explore how the Draco's natural characteristics interact with the LED element. It could also have themes of discovery, as the owner discovers new things about their LED Draco pet.

Well, in the fanfiction, they could have a very close relationship. Maybe they protect each other from the dark forces at Hogwarts. They might share secrets that no one else knows, like about their family's hidden past or their own personal fears and dreams.