First appearance episode 2.
Yafuri's first few appearances his just observing Jirou. In episode 7, while Jirou is fighting off Oguis' henchmen, one heads toward Mimiko and kotarou. But they are saved when Yufuri suddenly appears and cuts the guy in half.

Yafuri: I'm a little late.
Jirou: Who are you?
Yafuri: It's nice to meet you, Gintou, Mochizuki Jirou. The consanguineous killer, the hero of the sacred war, the guardian of Old Blood, one who inherits the sage, Eve's bloodline.
Jirou: You are a Kowloon Child, aren't you? And also of direct lineage...
Yafuri: Yes. *lifts head up* My name is Yafuri Chao. During the sacred war, I personally received the fangs of Kowloon through the kiss of darkness. "I want to see Jirou again." She's been saying that these past 10 years. Sister Cassa, that is.
-End of episode 7-

Episode 8 - Jirou informs him that whether or not he committed any crimes, he must kill him because Kowloon Children are a threat.
Yafuri informs Jirou that they welcome him, since they survive on chaos. "It's boring w/o a worthy adversary around."
Then they fight, after Yafuri says Cassa is close by. Yafuri informs Jirou of his other reason for coming there, 'I want to fight you.' Yafuri manages to 'knock the wind' out of him.
Yafuri: So you don't feel like getting serious over a kid who's only been changed for 10 years, huh? *suppression team shows up* Yafuri leaves.

Yafuri sneaks up on Zaza, who informs him that Cassa has arrived. Yafuri asks if Cassa said anything, Zaza says 'not really.' Yafuri asks why Zaza doesn't ask what he was doing earlier. Yafuri tells him he was fighting Jirou, Zaza says he knows already, Yafuri question how since no one was around. Zaza says he could see through the eyes of Kabun's corpses or something. *ick* He tells Yafuri to not do it again, to value his life. Yafuri gets mad, and says: "If there hadn't been an interruption, I would have... Why do you and Sister think so highly of that guy?!
Zaza: You're jealous, huh?
Yafuri: *blush* Care to repeat that, Brother?! Are you looking for a fight?! *kicks a hole in one of the creates and bags of blood fall out*
Zaza tells him even if he continued to fight he wouldn't have won. That there's a long story behind that bloodline. Yafuri says he doesn't know about that. Zaza tells him to rest some rest, and Yafuri nods. Zaza then tells him to clean up his mess. XD

Yafuri vs Cain
The squad with Cain opens fire on Yafuri who uses the Hide hand (i think that's the wrong name) to stop the bullets. Cain tells him he has some skills, and then asks where his Sister is. Yafuri: Rather than my sister, why don't you consider me as you opponent? *grips his sword* You've got comrades here with you. I can finish them off first, right?
Yafurai cuts a hole through the roof of the building and escapes as a bomb denotes.
Cain chases Yafuri into a car junk yard. He uses some wierd technique to find out where Yafuri is hiding. "Damn wizard."
Yafuri intro duces himself to Cain. He draws his sword and they fight again. He even manages to cut Cain, who disrespects him only to get cut up a lot more. Then Yafuri decides to give a speech (should have finished him off, really :/ ) Cain laughs, gets up and tranformers into a a werewolf of sorts (Cain the Blue Wolf). Yafuri knows he's in trouble now. Yafuri gets his head stomped on several times.
<A room with 5 crosses, garlic, and six bottles of holy water>
Yafuri is chained to the farest Cross. A man asks if he is alright. Zaza is controlling the soilder, and drops another solder at Yafuri's feet and tells him to feed on him, so they can go meet up with Sister.

Yafuri's running through the street, when he suddenly notices a yellow Chinese Dragon in the sky.
Yafuri: That's the Dragon King of the East... <looks afraid for a moment and then> Either way, he's just a Black Blood. Zaza tosses Yafuri his sword as a boat comes closer. Yafuri is happy to see his brother. Yafuri boards the ship and asks where sister is. His brother says she's not there yet. Zaza mutters something about the Dragon King making his move and then yells at Yafuri to defend. It's Cain! Zaza tells him to defend properly, Yafuri says he knows. Yafuri tells his brother to speed up, but he can't go any faster. Cain leaps toward the boat so Yafuri jumps toward him, but Cassa comes in and knocks Cain into the water.

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