Youkai Gakuen no Mazoku
Rosario+Vampire x Yu Yu Hakusho
By: Tellemicus Sundance
Yusuke goes to Youkai
After Yusuke finally returns to Ningenkai and Keiko, Keiko insists on him finally going to high school and finishing his education. But there was no school willing to accept him since he'd long since dropped out of middle school and had dismal grades regardless. Then, just as she's about to give up hope, Keiko receives an acceptance letter in the mail for Yusuke to attend a place called Youkai Academy. Since there is only one available slot in the letter and no way to request for a transfer so she can be with him, Keiko resigns herself to not being able to accompany him. Still, she gets him to agree to call her and write letters every single day.
On the bus to school, he meets a human named Tsukune and strikes up an easy friendship with him. When they arrived through the tunnel, Yusuke quickly realizes that there was something supernatural about the place since it was absolutely overflowing with youki. It wasn't until he intercepted Moka and prevented her from crashing into Tsukune that he knew that this was an area/school for demons. Intrigued by his strange youkai/ningen scent, Moka bit Yusuke and was instantly smitten by his extremely potent blood; though she was almost knocked out by Yusuke on reflex to the attack. Once she'd come down from her blood-high, she apologized profusely to Yusuke, not wanting to alienate the source of her new favorite food. With reluctance, he accepted her apology.
After Tsukune finally realizes that he's in a school for monsters, he nearly freaks out from fear. But with some encouragement from Yusuke (and revealing he too used to be human), Tsukune calms down enough to try giving the school a chance. However, when Moka tries to befriend him, a big brute follows her with intentions of claiming her for himself. Yusuke beat him down when he started getting rowdy, with just a flick of his finger that sent him to the infirmary. Afterwards, the three of them became friends, especially after Tsukune finally grants his acceptance of Moka being a vampire and still wanting to be friends.
A few days later, Kurumu takes an interest in Tsukune and Yusuke when she learns that they were the ones who had caused Saizo to be sent to the emergency room. When she tries to charm Yusuke, she is dumbfounded to realize that her Allure doesn't affect him or Tsukune like the rest of the boys. She at first misinterprets their resistance as meaning they're already in love with someone else (Moka) and this drives her into a jealous rage. Confronting Moka, she warns her to stay away from them, attracting a large crowd in the process.
That evening, while Yusuke's off training, Moka tells Tsukune of the encounter, but Kurumu had been stalking Tsukune and saw them together. When she attacks, Tsukune pushes Moka to safety but unintentionally pulls the Rosario off and unleashing the angry Moka-ura. Ignoring Tsukune's cries to stop, Moka-ura begins savagely beating Kurumu in retribution for all the trouble she'd been causing Moka-omote. Attracted Moka-ura's youki release, Yusuke comes running and, seeing her beginning to mercilessly beat and threaten an already defeated Kurumu, he is forced to fight Moka himself. Though he's not quite as physically strong as Moka, he is still quite fast and agile in his human form, which allows him to save Kurumu from Moka's clutches. While she's distracted glaring at Yusuke, Tsukune is able to sneak up and reattach the Rosario onto Moka-ura's neck, catching her by surprise.
After Moka falls unconscious, Kurumu asks him why he was trying to protect her and Tsukune tells her that he believes she's a good person and that she probably didn't mean anything malicious by her actions, that he forgave her of them. In that instant, Kurumu fell helplessly in love with Tsukune. Later, when she recovered, Moka-omote apologized profusely to the three if them for her Ura-chan's behavior, fearing that she may have lost her only friends in Youkai Academy.