SgtMaj. Darè Kochak pilots an Armored Trooper in the Berkhoff squad, a five-man Gilgamesh Confederation unit renowned for its soldiers' high survival rates during the conflict against the Balarant Union. His assignment occurs under Melkian Information Ministry Intelligence Department operatives Fedok Wokkam and Kotta Ruske, who are conducting experiments on "abnormal survivors."

Kochak exhibits significant cowardice and reluctance in combat. During a mission to destroy a Balarant fortress in Manid Gorge, he fails to eliminate all enemy Armored Troopers. One surviving "Fatty" pilot activates a main cannon, causing a cave-in that kills approximately 1,500 Gilgamesh soldiers. Squadmate Gary Godan violently assaults Kochak for this negligence.

Secretly, Kochak acts as a mole for the Melkian Information Ministry, reporting to M7 base commanders Yugunt and Fuller. His espionage includes monitoring squad dynamics and participating in security operations against his own team when base forces attempt to eliminate the unit. He shows no concern when the squad is targeted with explosives in a polymer ringer liquid tank farm. Following the Gilgamesh military's withdrawal order for Galeade, Kochak executes both Yugunt and Fuller.

Later, Kochak attempts to betray Gary Godan when the squad is targeted by the Gilgamesh Purification Committee, demanding Godan's surrender at gunpoint. Fellow squad member Glenborash Doroca Zaki disarms him, thwarting the effort.

Kochak pilots a customized Scopedog Turbo Custom-ISS, matching his squadmates, in both standard and arctic camouflage. His narrative concludes without explicit details on his ultimate fate after the Berkhoff squad's missions on Galeade. Kochak's role appears exclusively within the *Pailsen Files* OVA narrative, with no documented appearances in other *Armored Trooper Votoms* media.