A year has passed since Yusuke returned to the human world after the first ever Demon Tournament and now no longer a Spirit Detective, he returned to his friends and with the proposal he made with Keiko, he is about to be a married man in less than a month. In that year, Yusuke decided to open a Ramen Noodle Stand and went back to school and graduated, just barely so that he can better his life and have money for the wedding. Even though he is happy that he is no longer part of the Spirit Detective business, he does feel that one day there may be a time he is offered a chance to come back for one last case, but with how things are going between the relations of both Humans and Demons, he feels it won't anytime soon. With the relationship between the human and spirit world has improved even though there are still some issues, there has not been an incident since, until…..

In the morning at the Human Demon Peace Center located near the cave where Sensui's hideout was and where the demons attempted to cross over, two employees enter the building. "So, did you catch last night's episode last night?" The winged demon asked her co-worker, who is a regular female. "I didn't get the chance to because I was busy with moving to my new apartment." She responded back. "I am glad I am away from the old one after that explosion, I didn't want to take another chance on it." "I can't blame you for that decision." The winged female siding with her. "When demons had arguments where I grew up, anyone or building near the fight were destined to get destroyed." "Some childhood." Juje pretending to be jealous. "Nah, I won most of those fights." Suki said back and both women laughed.

As they continued walking, they noticed the security guard was returning to his post, upset with himself. "Everything all right, Mito?" The winged demon asked. "No Ms. Suki, I can't get the conference room open even with my key and I really don't want to destroy the door, but I feel there is no choice for me." He responded and pulled out a hammer. "Maybe I can pick the lock for you instead." Suki offered. "Besides, I think you going back just when people are about to arrive is not a good idea." She added. "Okay, just let me know what the problem is." He said and the two women left to go to the conference room.

Both women arrived outside of conference room, Suki used her nail to pick the lock. "That was nice what you did for Mito." The human woman feeling the kind gesture. "Juje, if you known me this long, I actually have a thing for Mito, and hopefully that will give him the courage to ask me out." Suki told her. "Should have known." Juje, not surprised by this. Suki finally got the door open. "I wonder why the door was stuck." Juje asked as the two women entered the room but noticed a really bad smell. "Dear god did they leave food in here over night?!" Juje asked covering her nose, while Suki didn't as she knew what the smell was. "Juje, I need you to go to Mito and tell him to call the police." She told her, and without question, Juje did. "If it gets me out of the room then okay, and whoever is responsible for this is going to be sorry." Juje said as she ran out, leaving Suki in the room alone. "They already did." She countered Juje's last statement. She turns on lights and sees a horrific site. 6 humans and 6 demons, brutally murdered, torn open and blood all over the room. "My lord, who would do this type of thing?" She asked herself, feeling horrified with what she sees.

At Spirit World HQ, Koenma, still in his baby form, is looking and stamping through forms. "Ever since we didn't need a spirit detective after the peace deal that was made between humans and demons, things still appear to be chaotic." He said to himself. "But I can't complain since the paperwork has been less and less, so I guess things are okay." As he said that the door busted open, startling him. "What the-" He sees Jorge Saotome, still the same as he was, breathing hard as he was running. "Ogre, what is the meaning of this?!" Koenma angry. "Sir, we have a problem!" He runs in and hands Koenma a sheet of paper. "It's from the Human Demon Peace Center, and it doesn't look good!" Ogre concerned with what he read and hands Koenma the sheet of paper. A minute passes and Koenma drops the paper, terrified what he read. "12 people dead?!" Shocked by the number, Koenma only got a nod from Jorge. "And it was 6 demons, and 6 humans, and they forgot to add the pictures. Do you want me to show you?" Jorge asked, hoping Koenma would say no. Koenma only nodded, knowing he was going to regret what he was about to see.

After a few minutes passed, Koenma and Jorge were horrified by the crime scene photos. "What was the reason for this?" Koenma asked as he was disturbed with what he saw. "I don't know, but they left this message written in blood on the next picture." Jorge said and switch to the next picture, and it didn't take Koenma long to figure out what the message said. "Buy why him, what does he have to do with any of this?" He asked himself. "Sir, what do we do?" Jorge asked, concerned with what Koenma will do.

After a few tense moments, Koenma finally had something to say. "Where is Botan?" Koenma asked. "But her name isn't on the message." Jorge responded, only to get hit with a stapler by Koenma, hurting him. "I know her name isn't on it, you idiot!" Koenma now pissed. "I am asking, where is she?!" "I believe she is on an important assignment right now!" Jorge said as he removed the stapler that was left in his head. "Damn, I was hoping not to get her to send a message." Koenma embarrassed. "Get me Ayame!" He ordered. "We must get to Yusuke before whoever did this gets to him first!" Jorge, without hesitation, leaves the room to find Ayame. "I hope we get there before they get Yusuke." Koenma hoped.

Yu Yu Hakusho:

One Last Case

A/N: This is a full story but keep in mind that this will combine both the Anime and Manga. So, lets begin this story. And I do plan to do this in volume form.