In the fanfic, it might be a symbolic act. Licking the wand could represent a moment of connection or understanding between Harry and Draco. It could be that they are forced into a situation where they have to trust each other and this act is a sign of that newfound trust, leading to a deeper friendship or alliance.
Perhaps it's a comical situation within the fanfic. Harry, being his curious self, accidentally licks Draco's wand while they are in a heated argument and it causes some sort of magical mayhem, like the wands start to emit strange lights and sounds.
It depends on how it's written. If it's written in a more comical and innocent way, it could be suitable for a wide range of ages. But if it has any undertones that are too mature or inappropriate, then it wouldn't be.
One possible reason could be a moment of sudden realization. Maybe Draco realizes that Harry is in a dire situation where he needs the wand to defend against a common enemy. It could be a sign of a shift in Draco's character, from being an antagonist to having a moment of altruism.
He might face backlash from his own side. His family or the other Death Eaters, if it's set in that kind of context, could view his act as betrayal. They would likely be angry with him and might try to punish him in some way.
Well, it could be that the special wand is made specifically to counter a new and powerful dark magic threat. The wand - maker might have foreseen this threat and created the wand for Harry. The wand could have some sort of connection to Harry's destiny, like it glows when he is near something crucial to defeating the dark force. Harry then has to figure out how to use this connection to his advantage in his battles against evil.
Maybe Harry is exploring an ancient and mysterious part of the Forbidden Forest. There, an old magic causes his wand to turn into a sword. The sword - wand seems to have a mind of its own and leads Harry to a hidden chamber. Inside, he finds a prophecy that can only be unlocked by the sword - wand. As he tries to figure out how to use it for this purpose, he has to fight off various magical creatures that are guarding the chamber. Eventually, he unlocks the prophecy, which reveals a great danger coming to the wizarding world and he sets off on a new quest with his sword - wand to prevent it.
One possible plot could be that the girl is lost in a mythical realm where Cerberus guards. At first, she is scared of Cerberus, but gradually, through some kind of magic or special connection, Cerberus becomes friendly towards her and gives her a lick as a sign of acceptance.
Well, it could be about the character Skitter finding a magical wand that gives her new powers. Maybe she uses it to fight her enemies in a more powerful way or to solve some difficult problems in her world.
Perhaps in the fanfiction, the Basilisk has a hidden power that can only be unlocked by Harry's wand. A prophecy states that Harry must use his wand to unlock this power and use it for good. However, there are those who want to use the Basilisk's power for evil. Harry has to race against time to figure out how to use his wand to unlock the power and keep it out of the wrong hands. This would involve a lot of exploration of the Hogwarts secrets and battles against dark forces.
Well, one possibility could be that it was an accident. Maybe Hermione was in a rush during a spell - casting practice session and accidentally knocked Harry's wand out of his hand and it broke on a hard surface. Another could be that she was under the influence of some dark magic or a spell that made her lose control and break it in a fit of rage or confusion.
Well, perhaps it could be a fanfic where they are on a secret mission together. After getting dirty during the mission, they find a single shower area in an old, abandoned building. They have to take turns, but there are some magical artifacts in the shower that start causing strange things to happen. Harry might be the first to notice something odd, Hermione would try to analyze it, and Draco would be reluctantly involved.