|Occupation||Shiranui Corporation secretary (former)|
Shiranui Corporation CEO (usurped, former)
follower of Triple=Gillusion
Road Fight mastermind
|B-Daman||Left=Starion (co-owned with Ryoma)|
|Japanese Voice Actor||Hideyuki Umezu|
|English Voice Actor||Paul Cowling|
Genya's hair and eyes are a darker shade of purple than that of his son, in addition to a small goatee, along with his hair being differently styled. He also wears a pair of eyeglasses, in addition to an orange-red polo shirt over which he wears a black trenchcoat and white gloves with segmented fingers, in addition to a pair of gray boots. When taking on the alias of Agent Dark, he puts on a mask with a distinctive yellow eye on it, that has a green iris, and it also comes with an unseen voice changer.
Agent Dark is cold, greedy, power-hungry, cunning and loyal to Triple Gillusion. He is also appreciative of his son, though. Like most of his co-workers in the Shira Corporation, he had also desired the company's coveted CEO position. He is also intolerant of traitors, especially when in Crush! Dark's Ambition, Novu Moru reported his fraudulent activities as the Shira Corporation's CEO to the police. He is also knowledgeable in the ancient legends of Crestland, due to his family being descendants of the warrior who wielded Gillusion. Because of that, Dark also has a certain hatred for Spike Phoenix, for the Kylin's loss in that fateful battle centuries ago brought disgrace upon the Kokuji family, and if Gillusion had won, his family would've gained a significant amount of power within Crestland. He also saw anyone under Gillusion's mind control ability as tools for his malevolent ambitions.
Genya Kokuji had once served as the secretary to Bakuga Shira's father, who was the Shira Corporation's chairman at the time. However, he also coveted his boss' CEO position, for he sought the money to create deadly weaponry based on B-Daman technology, and to sell the weapons for profit. However, he needed enough power within the company to do this. He had Chairman Shira arrested on false charges after a speech about the company's 50th anniversary. From there, he would have Bakuga cast out, so that he could take the CEO position for himself and to proceed with his B-Daman-based weapon system, which would be funded illegally. He also sought to use the power of Spike Phoenix as a weapon.
- Genya (ゲンヤ) means Illusion while Ankokuji (闇黒寺) means Temple of Darkness. It alludes to him being a devoted follower of Gillusion and a descendant of the evil Kirin's wielder from the ancient battle.
- He and Genta's names share almost the same set of letters, except with Genya's name having a "y" instead of "t".
- Genya's characterization is similar with (and a combination of) the previous B-Daman main antagonists
- His masterminding of Road Fight which brought Crest Land and their B-Ders to a state of unrest is similar to the activities of the Dark Matter organization from the Super B-Daman manga.
- His fanatical devotion to Gillusion is similar to that of Marda Biarce for Marda B in Battle B-Daman.
- Him manipulating a young man to do his bidding which just like what Geldezar did in Battle B-Daman: Fire Spirits.
- Lastly and most notably; Genya being an evil adult and company secretary that usurped the position of CEO and had even created destructive weapons are all deadringers to Kyousuke Arasaki of Crash B-Daman.
- He is voiced in the Japanese version by Hideyuki Umezu.