Koya (Japanese: コウヤ Kōya) is a character in Pokémon Diamond and Pearl Adventure.
Template:Spoiler In Volume 6, During the Sinnoh tournament, Mitsumi and the champion Cynthia have a Pokémon battle. When the fight gets a bit dangerous, the spectators move out of the front seats, leaving just Hareta and Koya with his Absol. Hareta then asks Koya if he would battle with him. Koya agrees after he sees Hareta's Empoleon. Koya uses Absol's Sucker Punch and ends the battle, claiming that Hareta was not worth battling. As he turns to leave, Hareta uses Empoleon's Surf to attack Absol, but it is frozen solid by Mitsumi's Glaceon. Koya tells Hareta that he will be waiting for him in a real tournament battle and leaves.
Koya later battles with Jun, and defeats him with just his Absol. After the battle, Koya harshly tells Jun that people like him have no right to be Pokémon trainers, and that he has no talent. Hareta stands up for Jun and claims that he will beat Koya.
Koya and Hareta make their ways up to the Semifinals of the Sinnoh tournament, where they have a Pokémon battle. They battle fiercely, and Hareta claims that battling Koya is "awesome fun". Koya then has a flashback of his past. It is revealed that he once had fun as a trainer, and battled alongside his Growlithe. One day, he challenged a Gyarados and was brutally defeated by its Surf. Growlithe was traumatized by the powerful move, which resulted in losing its courageous spirit. Koya then leaves Growlithe at the Pokémon center to become a member of the International Police. The flashback ends, and Hareta and Koya continue battling. Meanwhile, a member of the International Police, Agent Hansom, tracks down Kaisei, Hareta's father, who is watching his son battle. Hansom discovers members of Team Galactic and calls Koya in the middle of his battle with Hareta, informing him that Team Galactic and Kaisei are in the stadium.
The many members of Team Galactic in the stadium start to send out their Pokémon. They announce through the microphone that they are now called "Neo Team Galactic". Mitsumi talks to one of the grunts and finds out the name of their leader, Charon, and that there's a super-high-powered bomb planted in the stadium. Hareta digs up the bomb and proceeds to blast the bomb into the air using Brine. The grunt says that if he pushes it up into the air, the whole town will catch on fire. Koya then uses his Metagross's Light Screen to soften the impact. Everyone in the stadium pitches in and uses their Pokémon's Light Screens to surround the bomb. The town is saved and Hareta thanks Koya for the idea of using Light Screen. After this is over, Koya tells Hareta, "We'll finish this later." and leaves with Agent Hansom to capture Kaisei.
In Volume 7, Charon captures Mitsumi, Hareta, and Mars, while attempting to capture a legendary Pokémon, Heatran, inside Stark Mountain. Koya arrives with his Metagross to arrest him. The mamgma stone accidentally moves, awakening Heatran. Charon runs outside, finding Agent Hansom. Hansom gets distracted by shaking in the mountain, and Charon escapes. Inside, after a tossing and rolling the magma stone for a long time, they finally return it to its rightful place, calming Heatran. They soon escape the mountain, where they find Agent Hansom. He asks Koya if he saw any more members of Team Galactic inside. Koya lies, saying he didn't find any more members, allowing Mars to escape, having saved him inside from falling boulders. Koya and Agent Hansom leave to capture Charon afterwards.
Later, Mitsumi, Hareta, and Jun come across the grunt from Team Galactic who got bit on his butt by Hareta, B-2. They team up and go to a building where Charon is keeping Cyrus, the Leader of Team Galactic who went missing after losing his position to Charon. Koya is standing outside on the steps, and tells them that the International Police are inside raiding the building. Koya gets a call from Agent Hansom, who tells him that the operation is a failure. They walk to the top of the steps, where they find that every last agent has been defeated by Charon's army of Pokémon. Koya and Hareta prepare to go inside and face Charon, who is planning to capture Giratina.
In Volume 8, Koya and Hareta enter the Neo Team Galactic building, finding that the Pokémon were being controlled by a special machine. They enter a room where Charon is waiting with Koya's Growlithe, who is being controlled by one of the machines attached to its back. Hareta hears Growlithe "talking" to him. He uses Empoleon's Surf to remove the machine, and Koya is happily reunited with his Growlithe. Kaisei comes in and tells everyone, including Charon(Kaisei thinks he is one of the good guys because Charon fed him), that Giratina can be found in the Distortion World, and you can get there through Turnback Cave. Then Koya, Hareta, and Jun follow Charon into the Distortion World.
When they are inside the Distortion World, they find Giratina, full of anger. They find Kaisei, who has fainted. He wakes up and explains Giratina's behavior. He says that it is because Team Galactic tried to shoot Giratina with the machine that controls Pokémon, and when Kaisei blocked the attack, he passed out, and Giratina was outraged. Hareta sends out his Regigigas, and battles Giratina. Giratina brings everyone out out of the Distortion World, then Dialga and Palkia appear to help Hareta battle against Giratina. After a lot of battling, Mitsumi, Cyrus, Mars, Saturn, and Jupiter appear to help. Hareta suddenly decides to fight alongside Giratina, as he wants to learn more about it. After a while, Hareta says farewell to Dialga, Palkia, and Giratina, as they return to their own worlds.
Meanwhile, Kaisei leaves, and Charon is found by Agent Hansom. He informs Charon that Cyrus has agreed to disband Team Galactic, so he has nowhere to run back to. The Volume ends as Koya and Hareta continue their Semifinal match.
In the Pokémon Diamond and Pearl Bonus Story: Hareta's Future, Hareta is in his home forest, and is visited by Koya and his Growlithe. Koya asks him if he wants to join the International Police. Hareta runs off, accidentally running over Mitsumi. She tells him that Professor Rowan said, "Go forth and meet all the different Pokémon in the world and fill this National Pokédex!", and gives him the National Pokédex. Hareta agrees to travel with her, and changes into his street clothes. Hareta, Mitsumi, and Koya then set out on a brand-new adventure.
This listing is of Koya's known Pokémon:
|Growlithe first appeared in a flashback. At first, Koya did not care about winning or losing, until Growlithe was brutally defeated by a Gyarados which changed Koya's attitude of battling forever. After that, he left Growlithe at a Pokémon Center and went to join the International Police. When Koya and Hareta were dealing with the Neo Team Galactic situation, they found Growlithe being controlled by Charon. Koya got it back when Hareta used Empoleon's Surf to remove the machine controlling Growlithe.|
|Debut||Hearts and Spirits Collide|
| Before the match between Hareta and Koya, Hareta decides to pet his Absol. Koya then demands him not to. Absol may be Koya's main Pokémon as it was the only Pokémon (other than Growlithe) that was used outside of the Pokémon League and was used more often.
In Hareta's Heart's Desire, Absol was used against Jun's Pokémon including his Torterra. It was able to defeat Jun's Pokémon without any problems.
It was used again when Hareta's Luxio was out on the field. It almost defeated Luxio when it was covered in the rubble completely from Absol's attack. Doing so resulted in Luxio evolving into Luxray. It then defeated Absol.
|Debut||A New Battle Begins!|
|Metagross first appeared along with Absol prior to Jun's battle with Koya. It was only seen battling Hareta's Regigigas and lost. It was also used then to protect everyone from the bomb with Light Screen.|
|Debut||A New Battle Begins!|
| Mamoswine was used in the battle against Hareta. It was proven to be very powerful as it took out Hareta's Regigigas in one hit despite Regigigas being a legendary Pokémon.
It was then used against Hareta's Empoleon after Koya's Metagross got defeated by his Regigigas. Mamoswine used its speed to try to get the best of Empoleon using its Snow Cloak ability after using Hail. However, this was not enough as Hareta's quick planning took advantage of Mamoswine.
|Debut||Hearts and Spirits Collide|
|Japanese||コウヤ Kōya||Possibly from kō, the on-yomi reading for 光 (light).|
|English||Koya||Same as Japanese name.|
|Chinese (Taiwan)||小康 Xiǎo Kāng||From 康 kō (healthy/peaceful).|
|Pokémon Diamond and Pearl Adventure! characters|
|Hareta • Mitsumi • Jun • B-2 • Koya • Kaisei|