Sasuke Uchiha in Harry Potter

Horcrux

Sasuke wasn't in the mood to listen to the headmaster's speech, so he went to the seventh floor, taking advantage of the fact that everyone was in the Great Hall, to check out the information Luna gave him about the Room of Requirement.

While walking along the seventh floor, Sasuke thought he needed a room to store some things. After making three turns, the door appeared. Sasuke entered and saw the room filled with objects.

Sasuke: I guess this is the students' junkyard, he thought.

He took out a storage scroll and unsealed it, revealing several ninja weapons: Kunais, Shurikens, and Katanas. Sasuke stored them in an empty chest he found.

Sasuke: It's always good to have more weapons. You never know when they might come in handy, he thought. As he walked, he felt something calling to him but couldn't detect any presence.

Sasuke: Well, I have nothing better to do right now. I'll check this out, he thought, performing hand seals and shouting, KAGE BUNSHIN NO JUTSU. Ten clones appeared and began searching for the source of the voice.

After an hour of searching, they finally found it. It was coming from a box, and when they opened it, Sasuke was surprised to hear the voice coming from Ravenclaw's diadem.

Sasuke remembered that Luna's father said the diadem granted wisdom to its bearer.

Sasuke: Maybe with this, I can find a way to return to my world. It might also help Daphne with her sister's problem, he thought.

He put on the diadem and felt a sharp headache. The Horcrux was trying to possess him. It was easily breaking through Sasuke's mental defenses, but suddenly, a purple, skeletal hand blocked the invader's path.

The Horcrux tried to pass the block but couldn't, then it heard footsteps approaching.

Sasuke: So this is what's inside the diadem.

He continued approaching Voldemort's Horcrux and asked who he was, as he seemed familiar.

Horcrux: How is it possible that you are inside your own mind?

Sasuke: Why, because it's my mind.

Sasuke: I'll ask one more time, who are you?

Horcrux: My name is Voldemort, and now I'll take over your body.

...

Sasuke vanished from Voldemort's sight and reappeared, delivering a kick that sent him flying.

Sasuke: What were you saying?

Horcrux: What's happening? How is it possible that I'm feeling pain?

Sasuke: Come on, why don't you disappear like before?

Voldemort's Horcrux remained silent, glaring at him with hatred.

Sasuke: You can't, can you? You're just like Tom Riddle's diary. Wow, how could I forget about you? You're so insignificant you weren't worth remembering, Tom.

Horcrux: My name isn't Tom.

Sasuke: You can't use magic, can you? You can only do it by possessing a body.

Voldemort clenched his fists.

Sasuke: Now you're going to tell me everything—what you are and how many more of you exist, he said, activating the Sharingan.

Horcrux: What are those eyes? What are you?

Sasuke: I'm a shinobi. Looks like you can still use Occlumency since it doesn't require a wand.

Horcrux: You won't get any information from me, Shinobi.

Sasuke: Heh, you'll tell me everything. I just need to weaken you so you can't use Occlumency.

Horcrux: Don't underestimate me, he said, charging at Sasuke to fight.

Sasuke easily dodged with his eyes closed.

Sasuke: Seriously, have you ever fought before?

Voldemort kept trying to punch Sasuke while yelling at him to shut up.

Sasuke: That's one of the weaknesses of wizards. They only strengthen their magic, not their bodies. What's the point of so much magic if a single blow takes you out of the fight?

Voldemort kept striking, but without success. Until he managed to hit Sasuke square in the face.

Voldemort smiled with satisfaction.

Sasuke: Is that it? You only managed to hit me because I stopped dodging—what a disappointment.

Voldemort stepped back, and his entire body began to tremble.

Horcrux: What is this? What is this feeling?

Sasuke: You must be wondering what this feeling is, right? That feeling is called fear.

Horcrux: Fear? No, it can't be. You're lying.

Sasuke: Then why won't your body stop shaking? Anyway, I'm tired of this game. It's time to finish this.

Sasuke ran at high speed and punched Voldemort in the face. He didn't stop and kept hitting him with both hands. When Voldemort was about to fall backward, Sasuke appeared behind him and kicked him. He started being hit from all sides, unable to do anything to defend himself.

Voldemort tried to counterattack, but his blows were easily dodged. For every punch he missed, Sasuke retaliated with two more. He was hit so many times he started coughing up blood.

Voldemort tried to flee, running in the opposite direction, but Sasuke appeared in front of him and landed a blow to his stomach.

Voldemort dropped to his knees, clutching his stomach in pain. Sasuke grabbed his head with one hand and smashed it against the ground with such force it created a small crater.

Sasuke grabbed Voldemort by the nape and lifted his head. He was unconscious, his face all bruised and bleeding profusely.

Sasuke: Is this all you are? A pathetic being. Now, you'll tell me everything I want to know, he said, prying Voldemort's eyes open with his other hand, staring at him with the Eternal Mangekyou Sharingan, sending him into a genjutsu.

Sasuke: What are you?

Horcrux: I am a Horcrux.

Sasuke: What's that?

Horcrux: A Horcrux is a very powerful object in which a wizard conceals a fragment of his soul with the purpose of achieving immortality.

Sasuke: How do you split a soul?

Horcrux: You must understand that the soul must remain intact and whole. Splitting it is an act of violation; it goes against nature. The wizard must commit an act that defies nature, something that corrupts the natural order of things, capable of mutilating the soul—murdering a human being.

Sasuke: This guy reminds me of Orochimaru, he thought. How many more exist, and where are they?

Horcrux: I only know of the Horcruxes I created before my rebirth.

Sasuke: Speak.

Horcrux: My diary—Sasuke interrupted him, telling him to move on to the next.

Horcrux: Marvolo Gaunt's ring is in a cabin located in the forest surrounding the village of Little Hangleton.

Horcrux: Salazar Slytherin's locket is in Devon, in the caves of Torquay. Those are all the Horcruxes I know of.

Sasuke used Amaterasu to turn him to ashes. Upon leaving his mind, he removed the diadem.

Voldemort returned to the diadem, utterly humiliated. In his mind, he said he needed to sleep to recover.

Sasuke looked at the diadem and still felt Voldemort's presence in the object. He cast another Amaterasu on the diadem. A horrific scream echoed throughout the Room of Requirement as the diadem was reduced to ashes.