Well, in some 'Harry Potter plays truth or dare fanfiction', there might be a scenario where Harry is dared to ask Snape a very personal question as a truth. This would be quite nerve - wracking considering their relationship. Hermione could be asked to tell the truth about which of her friends' habits annoys her the most. And Ron might be dared to wear a girl's robes for a whole day at Hogwarts, leading to a lot of laughter and embarrassment.
Obviously, Harry, Hermione and Ron are the most likely. They are the main characters and are always together, so it's natural for them to be playing truth or dare. Neville could also be involved as he's their friend. And Ginny might join in too, especially as she gets older and becomes closer to the group.
Grover could be another main character. His reactions to the crazy dares and truths would add a lot of humor and charm to the fanfiction. He might be the one to try and keep the game somewhat civilized, but fails miserably.
One idea could be to have the characters play Truth or Dare in the Gryffindor common room. For example, Harry could be dared to sneak into Snape's office and steal a potion ingredient. Another idea is to set it during a holiday at Hogwarts, like Christmas, and the students are using Truth or Dare to pass the time. They might ask Ginny about her first crush, which could lead to some really interesting revelations and interactions among the characters.
To make it engaging, add some unexpected twists. For instance, when a character is asked a truth, they give a really shocking answer that no one expected. Like if Ron is asked about his worst fear and he reveals it's not spiders but something much deeper. Also, for dares, make them challenging yet possible within the wizarding world. For example, daring Cho Chang to fly on a broomstick through a difficult obstacle course set up in the Quidditch pitch.
Harry Potter himself is often a popular character in such fanfiction. His adventures and the secrets he could potentially reveal in truth or dare make him interesting. Hermione is also popular as she has a lot of knowledge and secrets. Ron, with his humorous nature, is another common choice.
One interesting scenario could be when a character is dared to go into the Forbidden Forest at night. It creates a lot of tension as the forest is full of dangerous creatures. Another could be a truth where a character has to reveal their deepest fear about Voldemort. And there might be a dare for a student to sneak into Snape's private chambers.
One great 'Harry Potter Truth or Dare Fanfic' is 'The Great Hall Games'. It has really interesting scenarios where the characters are put in tricky truth or dare situations that are true to their personalities. For example, Hermione has to face some really tough truth questions about her studies and her feelings for Ron, which makes for a very engaging read.
A really exciting 'Truth or Dare' scene might involve the Slytherin students challenging the Gryffindors. A Slytherin could dare a Gryffindor to enter the Forbidden Forest at night. This not only tests the Gryffindor's courage but also creates a tense and exciting moment in the fanfic.
The most interesting part is seeing how the characters' personalities are explored. For example, Hermione's logical mind might make her choose 'truth' more often to avoid risky dares. And Harry, being brave, might take on the most daring dares. It gives a new perspective on the characters we already know.