One way is to have the character enter the dark tunnel while fiddling with the hair tie on their wrist out of nervousness. Maybe they find something in the tunnel that makes them realize the importance of the hair tie, like it was a key to unlock a hidden door.
The character could be running from danger and hide in the dark tunnel. They notice the hair tie on their wrist and remember it was given to them by a person who always told them to be brave. This gives them the courage to face whatever is waiting for them in the tunnel. In a sci - fi fanfic, the hair tie could be made of some advanced material that helps them in the tunnel, like it glows to light the way.
In a fanfiction, you could start with the character lost in the dark tunnel. They feel around in the darkness and touch the hair tie on their wrist. This gives them an idea. They could use the hair tie as a sling to throw a small object and make noise, hoping to attract help. Or perhaps the hair tie has a pattern on it that is a clue to a mystery within the tunnel. It could lead them to a secret passage or a treasure.
The character could be in the dark tunnel, feeling lost. They look at the black hair tie on their wrist and remember a promise they made. This memory gives them the motivation to keep going and find a way out of the tunnel. For instance, if it was a promise to a friend who is in danger, the hair tie serves as a reminder of their duty.
In fanfiction, a dark tunnel might symbolize mystery or a journey into the unknown. The hair tie on the wrist could be a simple accessory with a deeper meaning. It might be a reminder of someone, like a love interest who gave it. For example, in a supernatural fanfic, the dark tunnel could be a portal to another dimension and the hair tie could be a charm that protects the character as they enter it.
The black hair tie on the wrist can be a part of a character's transformation. Suppose a shy character decides to take off the hair tie from their wrist and tie their hair up, signifying a newfound confidence and a change in their attitude towards a situation in the fanfiction.
Perhaps it symbolizes a form of restraint or hidden power. The black hair tie on the wrist is a physical object that can be used to hold things together, like hair. In the context of the fanfiction, it might suggest that the character is holding themselves back or has some latent ability that is 'tied' up. The dark tunnel could be the place where this hidden aspect of the character will be revealed or challenged.
It could be a clue. Let's say a character goes missing in the fanfic, and all that's left behind is a hair tie on the wrist. The other characters then have to figure out who the hair tie belongs to and what it might mean in relation to the disappearance. This could lead them on a journey of discovery through the town and its secrets.
One way is to have it be a key to a mystery. Maybe it has a hidden mark or inscription that leads to a secret location or treasure. Another way is to have it be a tool for a Pokemon's evolution. The trainer uses the hair tie in some special way to help their Pokemon evolve.
Such a description might be used to make the character stand out in a fanfiction. He could be a unique character in a fantasy - based fanfic too. For example, he could be a wizard who has adapted to some modern - day human habits like wearing a hair tie on his wrist. His bun could be a way to keep his long hair out of his face while he's performing magic.
The fact that her hair is in a bun might also play a role. It could be a cultural or traditional style in the fictional world she belongs to. When she's kidnapped, her captors might be disrespectful of this style, which angers her and gives her the motivation to resist. The bun could also be used practically during her captivity. For example, she might hide small objects in it to help her escape, like a lock pick or a small note.
In fanfiction, a girl with a dirty hair tie on her wrist could be a sign of her being in a hurry or perhaps she's been through some sort of adventure. Maybe she was so caught up in an event that she didn't have time to clean up or change her hair tie. It could also be a unique characteristic given to her by the author to make her stand out. For example, in a fantasy fanfiction, it might be a charm that has some special power but just looks like a dirty hair tie.
One possible plot could be that the hair tie has some sort of magical or sentimental value. Maybe it was given to the main character by a loved one. A villain kidnaps it to try and manipulate the character into doing something. The character then has to embark on a quest to get it back, facing various obstacles along the way.