Kasumi (Castle Dusk)

or, is a princess of Castle Dusk that appears on Naruto: Ultimate Ninja Heroes 2: Phantom Fortress.

Appearance
She had the appearance of a priestess with long black hair, and wore a white kimono along with a curse mask with a red snake on the left side that was given to her by Orochimaru. The hair ornament she wore was a gift to her from Jiraiya, the bellflowers representing "gratitude", which the player can discover when playing Jiraiya's side of the story.

Abilities
Kasumi can easily make someone fall into an illusion, using her mask, which feeds her hatred. She also has the ability to disable the dōjutsu while the user is inside the castle. Her powers also allow her to sense approaching shinobi with ease, as she is intertwined with the castle. Her power also permits her to turn illusions into reality (as she created Gaara's copies and attacked Naruto Uzumaki).

Plot Overview
After the Mugen Castle was summoned in Konohagakure late one night and Naruto went to investigate, Princess Dusk appeared to him, Sakura Haruno, Shikamaru Nara and Hinata Hyūga after freeing Kiba Inuzuka from her control. She complained about Kiba's abilities, and then turned her gaze to Naruto. She left, saying that she would "never forgive them", although she didn't say what they had actually done. After they found the first summoning tag that had been used to summon the castle and peeled it off, Naruto and the others saw a vision of a girl named Princess Kasumi giving one of her guards and maid-in-waiting a lucky charm for everything they had done for her. Inside was a note which showed that she had cared more about them than she did herself. When Princess Dusk detected this, she created more illusions to stop Naruto and his friends from progressing any farther into the fortress. Later on, they found a Chōji Akimichi's illusion that she had created alongside an Ino Yamanaka's illusion, but they were defeated after the real Ino and Chōji arrived.

When Naruto and his friends reached the second seal and peeled it off, they saw another vision of Princess Kasumi giving a ribbon from when she was a child to a young girl. After that, Princess Dusk appeared again, saying that peeling off the seals only ensured the village's doom. Every time a seal is peeled off, the castle will work harder to stay alive meaning she and the castle will have to absorb more vitality from the life in the village. Not willing to give up, Naruto said that he would rescue the village at any cost. The princess claimed that his actions were useless, and created a Gaara illusion. However, after Naruto defeated it, she summoned it back again, only for Naruto to defeat it again. She then created multiple Gaara copies to attack Naruto, which were quickly destroyed after Kakashi arrived and defeated them all with Lightning Cutter. After Kakashi's arrival, Princess Dusk disable Kakashi's Sharingan and laughed while slowly fading. She commented as she fled "It's useless to use such trickery on me".

Thanks to Kakashi removing the third seal, Naruto and the others moved on to the fourth seal and removed it. They saw Princess Kasumi pledging to make Castle Dusk, her home, full of happiness and laughter. Just then, the three people she gave gifts to before returned the favour and gave her a music box. As she enjoyed the song it played, Naruto and the others returned to the castle. Kakashi explained that the visions they were seeing were really the sealed memories of Castle Dusk, which was now the Mugen Castle that Naruto and the others were in. Every time they removed a seal, the memories escaped from the castle walls.

While everything they saw so far was good, after meeting up with Might Guy, saying that he had removed a seal, things turned for the worst. After they found and removed the sixth seal, they saw a vision of the castle ablaze with fire, with the inhabitants being killed due to an attack from Konoha. After seeing this, Princess Dusk arrived, filled with hatred towards Naruto and the others. She summoned an Itachi Uchiha's illusion, and sent it to fight. After it was defeated, she fled once more. Soon enough, Shikamaru put the visions they saw together, along with Princess Dusk's words, and they discovered that Princess Dusk was actually Princess Kasumi.

When Naruto reached the seventh seal, he stopped to question his actions. However, thanks to Kakashi returning after meeting Jiraiya, they peeled off the seal to discover the real attacker. Princess Kasumi's home had really been attacked by Orochimaru. He had tempted the princess to wear a mask, the same one Princess Dusk now wore, saying that it would grant her tremendous power. But, as long as her hate lingered, her mask would never come off, and her spirit would be infused with the castle. Enraged by Orochimaru's deceitful tricks, Naruto went to find Princess Dusk to tell her the truth. But words alone wouldn't make her see reason, and she sent Kisame Hoshigaki and Shizune's illusions to battle them, both of which were defeated. Thanks to the help of the three other beings from the visions, Naruto and the others found the charms, the ribbon and the music box, items that had meant a great deal to Princess Kasumi when she was still alive. When they approached Kasumi and showed her the ribbon and charms, her mask began to crack.

She escaped after attacking them with more illusions. However, while she was recovering, Kabuto arrived, threatening to seal her soul in a scroll if she failed to defeat Naruto's team one last time. She ultimately failed again, after which Naruto showed her the music box. Her mask cracked some more, and she started to regain control of herself. Kabuto arrived after she had fled, and prepared to seal her soul. Naruto chased after Kasumi, knowing that he was close to completely breaking the mask. When he arrived, Kabuto paralysed him with a Genjutsu Binding. Naruto fought his hardest, however, and jumped in front of Kasumi, taking the hit of the technique and having his vitality sealed into Kabuto's scroll. Kasumi asked why Naruto would do this, to which he replied that she wasn't his enemy. He also mentioned that it was his ninja way to protect others. Just as Kabuto planned to kill him, Gaara arrived and fought him off. Kakashi stayed behind to help Naruto as the others chased after Kabuto. Gaara caught Kabuto and got the scroll back. Naruto's vitality was freed, and he returned Kasumi's music box to her. It was that moment that her mask fully shattered, and her real face was revealed. She then joined them in destroying the castle.

After they headed to the castle's top floor to finish their mission, Kabuto arrived with an illusion of Tsunade, showing that Kasumi had never been the one controlling the illusions in the castle. She had merely channelled them as the castle absorbed vitality. Naruto and Kasumi pushed on ahead as everyone else stayed behind to face Kabuto and the growing illusions. Naruto found the last scroll, with Kasumi's real body trapped in a crystal. However, Orochimaru suddenly appeared to tell Naruto that he was too late. Naruto faced Orochimaru twice, once as normal and the second time using the Nine-Tails' chakra. After he managed to defeat Orochimaru, it was revealed to be an illusion. Naruto, using what little chakra he had left, as well as the faith of Princess Kasumi and everyone from Castle Dusk along with his friends, used a powerful Rasengan to shatter the crystal and destroy the Mugen Castle for good.

After that, Naruto bid farewell to Kasumi's spirit after thanking her for the wish just as the castle began to crumble. When everything was back to normal, Tsunade sent Team 7 on a "special" mission. When they arrived at their objective, it was revealed to be a beautiful field of flowers. Kakashi explained that this field was where Castle Dusk had once stood, and how it had been a barren wasteland until the Mugen Castle had been destroyed. As their mission was to discover why this had happened, Naruto looked up towards the sky, having a hunch, and with a smile on his face. He believed that this was Kasumi's work, and her last words before fading away completely were "Thank you…".

Trivia

 * Through she doesn't make a physical appearance, Princess Kasumi is mentioned in Naruto Shippūden: Ultimate Ninja Storm 2 through a series of letters that Naruto will get after obtaining the Book of Mugenjo, a direct relation to the Mugen Castle, the setting of the game she appears in. Each time Naruto receives a letter from her, all it says is that a gentle, familiar breeze is felt.
 * It's also possible to meet Kasumi in Naruto Shippūden: Ultimate Ninja 5.