In a house, a mother is seen washing dishes. Then a little white haired boy was running up to touch her mother. That child was Kurobe.
Mother: Kurobe, don't run in the kitchen.
Kurobe: But mother, I want to be a hero, to defeat the demons!
Mother: Maybe, now you have to behave like a normal kid. Also your father will return for the family trip.
Kurobe: Yeah, I'm excited!
At that moment it's heard a crying baby.
Mother: Oh, your little sister woke up. Kurobe, can you play with her, I'm busy.
Kurobe: Yes.
Then Kurobe went to a room, there was a crib. A white haired baby girl was crying. Kurobe was in front of her.
Kurobe: Shiromi, I'm here, don't cry.
The baby girl was calmed as looking to him. He gave his hand to her.
Kurobe: (Smiling) Don't worry Shiromi. Your big brother will protect you, because I will be a hero.
The baby touched his hand as being happy. It was a siblings moment.
Kurobe: I'll be a hero.
Suddenly the scene turned into a car accident on fire, the car was into pieces. Also other cars and people corpses were everywhere on the road. Kurobe was injured and afraid about the situation.
Kurobe: (Afraid) Mother? Father?
He saw his parents were dead. Their corpses on the road.
Kurobe: (In shock) No. Shiromi?
He saw the crib was empty and covered by blood. Then he saw a human shadow.
Kurobe: (In shock) NOOO!
He screamed in horror as turning into black. Then Kurobe woke up, he had a past dream. He was resting at side of a tree. The other girls were sleeping in a tent.
Kurobe: Damn! That dream again?
Yuki woke up and come to him.
Yuki: Kurobe, are you okey? You had a bad dream.
Kurobe: It's nothing.
Then Tsubaki woke up and was sleepy.
Tsubaki: (Sleepy) Hey, why are you making too noise?
Kurobe looked at her but then he blushed and looked away.
Yuki: (Funny amazed) Hey Tsubaki! Why did you wake up like that?
Tsubaki: What?
Then she realized she was in sleeping clothes but her shirt was unbuttoned. It's seen her cleavage was very clear to them. She blushed and run away.
Tsubaki: (Embarrassed) NOOOOOO!
Later; Kurobe and his group was arriving to a big city.
Kurobe: Look! We arrived to Vermillion city.
Luna: What city is that?
Kurobe: It's an advanced tech city, similar to Neo Japan.
Tsubaki: Good! I'm tired for walking by days!
Yuki: We can rest here for a while.
Kurobe: Be alert. We don't know when more demons will come here.
Tsubaki: But we need a good rest! I want a shower!
Kurobe: Fine, let's go.
They were walking as many people were looking at them, mostly to Luna.
Yuki: As always Luna is the center of attention.
Tsubaki: Why do you wear those indecent clothes? It's too relevant.
Luna: Why? Other beast races don't wear any clothes.
Kurobe: (Funny amazed) Eh?
Tsubaki: Pevert demon!
Kurobe: No! I wasn't thinking about that!
Luna: I don't mind. (As moving her hips and tail) also this outfit is light for combat.
Tsubaki: That's weird!
Luna: Weird? For someone who's wearing a school uniform for trip.
Tsubaki: This is my like! Also I won't ever use that outfit. I want to take a shower.
Then Kurobe and his group reached at a hotel. He was reading a book. Yuki and Luna were playing chess. Tsubaki was taking a shower.
Kurobe: I think I'll walk through the city.
Yuki: You should take Tsubaki.
Kurobe: What? Why?
Luna: It's a chance you two get along better.
Kurobe: But.
Yuki: We'll be fine.
Next, Kurobe and Tsubaki were walking together.
Tsubaki: (Little blushed) Don't think this is a date!
Kurobe: Yeah, we should get along.
Suddenly a little kid crash with him.
Kurobe: Hey!
Little kid: Sorry!
Tsubaki: Be careful kid.
Little kid: Sorry, onee-chan.
Tsubaki was stroking his hair as calming him.
Kurobe: You're good with little kids.
Tsubaki: Well, I was unique daughter so I had to interact with kids in past.
Kurobe: Yeah, that's nice.
Some women were watching them.
Women: Oh my, what a nice family. A father and a mother caring with their child.
They blushed to hear that, mostly Tsubaki.
Tsubaki: (Blushed) Father? Mother!
Kurobe: What was that?
Then a big kid arrived to them.
Big kid: Sorry, my little brother was running.
Little kid: Takuya Onii-chan, I was running to airport but I missed the direction.
Tsubaki: You two are siblings?
Big kid: Yeah, this is my little brother Takeru. I'm Takuya his big brother. Sorry about this.
Kurobe: (Amazed) Siblings?
Tsubaki: Are you going to a place?
Takuya: Yeah, we'll heading to airport. Our parents are arriving in some hours.
Takeru: Yeah! I want to see father and mother after months!
Takuya: Sorry for the troubles. Takeru, let's go.
Takeru: Yes. Sorry about before onee-chan, white haired onii-chan! Bye!
The siblings went to other place.
Tsubaki: Those siblings are nice. They must be happy to meet their parents. (Noticing Kurobe) Eh? Akatsuki?
Kurobe was in grief to hear those words.
Kurobe: (In his state) Siblings. Parents. (Remembering his family) Whatever.
Tsubaki: Are you okey?
Kurobe: It's nothing. Let's move.
At the hotel, Yuki and Luna were still playing chess.
Luna: Do you think Kurobe-san and Tsubaki-san will be okey?
Yuki: Yes, also they should get along, like Kurobe and me.
Luna: Boo! I wanted a date with Kurobe-san.
Yuki: Checkmate.
Luna: Eh?
Yuki: You should learn this more than just fighting.
At the city, Kurobe and Tsubaki keep walking.
Kurobe: So where do we should visit?
Tsubaki: It's a long time I walk in a big city. Maybe Luna was right, I have to buy new clothes.
Suddenly some explosions happened near to them.
Kurobe: That!
They run to a place, which is an airport. It's seen many scared people were running away.
Kurobe: The airport!
At a hideout; one of general demons was in front of her army. It was the female general demon. A red skin woman with horns.
Female general demon: So how's the plan?
Demon: Mavka-sama, some troops are attacking some villages and cities. We'll find that white haired boy!
Mavka: Good.
Demon: A troop is attacking the Vermillion city.
Mavka: You'd better find him for Satan-sama!
Demon: Yes!
At Vermillion city, some demons began the attack, mostly at the airport. Kurobe and Tsubaki arrived. A orc and some the demons focused on Kurobe.
Orc: Hey! That white haired boy! He's the target Mavka-sama was looking for!
Kurobe: So they are after me again!
Tsubaki: (Taking her sword) Let's finish them!
The demons attacked. Kurobe and Tsubaki used their weapons to counter.
Kurobe: You're after me? Don't attack other people cities!
Orc: We'll do anything to kill you! Satan-sama will see you were a failure! A human can't be the strongest demon like him!
Kurobe: I'm human but I won't be his puppet!
Then it's seen Takuya and Takeru were hidden. They were watching that battle.
Takeru: It's white haired onii-chan, and the onee-chan!
Takuya: Be quiet!
Kurobe realized their presence.
Kurobe: Hey you! Go away!
Then the orc run and catched them as hostages.
Tsubaki: Hey! Let them go!
Orc: Maybe you can stop your attack but that half-demon won't obey, so… let's find out!
Kurobe: (Pointing his shotgun to him) You're cheater!
Orc: Come on, shoot. But you won't care the life of those kids?
Tsubaki: Wait Akatsuki!
Kurobe was ready to shoot, but then he stopped.
Kurobe: (Angry) Shit!
Orc: Hahahaha! Since when a demon cares a human?
Takuya: (Scared) Why do this is happening to us?
Takeru: (Scared) I want mom and dad!
Kurobe: Don't cry Takeru. I promise you will see your parents!
Then more demons attacked them.
Orc: Kill them!
Suddenly, Tsubaki in a fast move attacked the orc, freeing Takuya.
Tsubaki: Are you okey?
Takuya: Yeah but what about Takeru?
Orc: Damn! That girl is very fast for being human. But you won't defeat me as long as I have this little kid.
Takeru: (Scared) Save me!
The orc jumped and disappeared with Takeru.
Takuya: (Worried) Takeru!
Tsubaki: Don't worry, we'll save him!
In a slash, Kurobe killed the rest of the demons.
Kurobe: Where's Takeru?
Tsubaki: It looks like he was taken to the high place of the airport!
Suddenly more demons appeared.
Tsubaki: Akatsuki, go, I'll handle them!
Kurobe: Fine, but you should call Yuki and Luna.
Kurobe jumped to the high place. Tsubaki was taking care of Takuya as more demons were surround them.
Takuya: Can you defeat all those demons alone?
Tsubaki: I don't know but I have to do it.
The demons were ready to attack but suddenly some of them were pierced by ice spikes and others were hitting by mortal punches.
Tsubaki: Yuki! Luna!
Its's seen Yuki and Luna arrived at time to save.
Yuki: Tsubaki, it's good you're okey.
Luna: We detected demon energy so we came here.
Takuya: (Amazed) Those girls are awesome!
Yuki: Where's Kurobe?
Tsubaki: He's after an orc who kidnapped a little kid.
Takuya: Yeah, he's my little brother! Please, save him!
Tsubaki: Yuki, Luna, take care of him. I'll go with Akatsuki.
At the airport high place, Kurobe reached there and saw the orc who was holding Takeru.
Kurobe: There you are! Let him go!
Orc: Do you defend this kid because you have human side? What will he think if he sees your other side?
Takeru: What is it meaning?
Orc: You fight me? Why you waste your time with other humans?
Kurobe: I told him they will see their parents! No matter what!
Orc: (Menacing Takeru with his hands) Come on! I'm not like those cowards who fails with a demon imitation!
Kurobe: (Angry) Damn! (Feeling pain) Ah! My power is out of control again! That monster has high level power! If I don't use this curse… but Takeru will be afraid of me… I have no choice… Sorry Takeru! But this is my other being!
Takeru: White haired onii-chan?
Kurobe screamed in rage, turning into his demon form. Takeru was in shock to see him.
Takeru: White haired onii-chan? You!
Orc: Hahahaha! This is your other side, now let's see if you dare to kill me along with this kid…
In an instant, Kurobe launched his chain spear piercing his head, releasing Takeru. Then his spear was moving and piercing the orc many times. Then it returned to his arm.
Kurobe: Go to hell!
Takeru was in shock to see Kurobe in his demon form, but then he turned back to his human form. Tsubaki arrived to see them.
Kurobe: (Sad) Takeru, sorry, you should be scared of me right?
Takeru: You're… (Amazed) Awesome! White haired onii-chan, you have demon power.
Kurobe: (Confused) What? Didn't you see me?
Takeru: But you don't act like those monster. I knew you're different.
Tsubaki: Right. I had my doubts too. He can be a pervert but he's a good, even he has demon power.
Kurobe: I expected a better description.
Suddenly the orc woke up and grabbed Takeru. Kurobe shot his shotgun to its head. But the orc was falling along with Takeru.
Tsubaki: Akatsuki! He's falling!
Kurobe run fast to them as their fall. The orc corpse was on the ground after fallng from a great height.
Tsubaki was going to the edge.
Tsubaki: Akatsuki!
She saw Kurobe was holding to a pole, as holding Takeru. Tsubaki tries to catch them.
Kurobe: Tsubaki, help him!
Kurobe gave Takeru to Tsubaki to help him. As she grabbed Takeru, the pole broke and Kurobe fall until crashed to the ground.
Tsubaki: (Worried) Akatsuki!
Takeru: White haired onii-chan!
Then Yuki and the others went to Kurobe who was injured but alive.
Yuki: Kurobe!
Kurobe: Don't worry, I fall but I used my demon form again for seconds to heal my injuries. I'll be fine I guess.
Luna: I'm glad you're okey.
Tsubaki: Don't scare like that again!
Takuya: Thanks for helping us. You are people with great skills.
Takeru: Yeah, white haired onii-chan also has monster power but he's good.
Takuya: Really?
Takeru: Yes, I'll tell you more later!
Takuya: Well, thanks for everything.
Later, the airport was working again as some workers were repairing some damages. The kids saw a plane arriving. They went to see some passengers; two of them were a married couple.
Takeru: Look onii-chan! Our parents!
They went to embrace their parents who were happy to embrace them.
Mother: Takuya! Takeru! My god! You're okey!
Father: Our flight was cancelled because demons attacked the airport! We were so worried for you!
Takuya: We're fine.
Takeru: Yes, white haired onii-chan and his group saved us!
The parents were little confused to hear that.
Takuya: We'll tell you everything later. Thanks to him the airport was saved.
Takeru: (In high voice) White haired onii-chan! Thanks wherever you are!
At other side of the city, Kurobe and his group were walking where there weren't many people.
Yuki: I'm glad those kids are able to see their parents.
Luna: Yeah I wished to meet them.
Kurobe: We are already taken too much attention. We shouldn't be here too much time. Vermillion city is too big. Let's find another hotel to rest, then we leave.
Tsubaki: Akatsuki, why did you insist of helping those kids? That's not normal from you.
Kurobe: Because they were siblings. Those reminded when I was a brother. (Imagining his kid self and his baby sister, holding hands as smiling) My sister died along with my parents in the past. I didn't want those passed the same like me.
Tsubaki: (Smiling) That's so nice.
Luna: Yeah, you're awesome, Kurobe-san.
Yuki: Right.
Kurobe: Alright enough, just let's keep going.
At a long distant, someone was watching them with tech binoculars from a building roof. It was a red haired twintails girl.
Mysterious girl: Oh? Those people have great skills, maybe they are adventures. But that boy, his energy is monstrous. I wonder if my high tech weapons can kill him.