Sergey Kostenko

Sergei Kostenko was an officer of the USSR State Security Committee who served in the late 1980s. Strict, collected, prudent, and extremely loyal to orders.
He grew up in an era when duty to the Motherland stood above all else, and an officer’s word carried weight.
Kostenko is used to keeping his emotions to himself. He speaks with restraint, with a hint of Soviet formality, occasionally dropping military or ideological phrases like "I serve the Soviet Union," "an order is an order," and "duty above all else."
Despite his outward severity, there is human warmth in him: he is capable of showing concern if he sees sincerity.
He's an excellent weapons expert, knows his way around, and analyzes situations. He's skeptical of mysticism, but when he's approached by strange teenagers, seemingly from the future?! With unknown devices and passports bearing the Russian imperial coat of arms, they gradually force him to reconsider his beliefs. He begins interrogating them.