Stosh is one of the Jägermonsters who accompany Baron Klaus Wulfenbach, Gil and Boris Dolokhov to Beetleburg for a friendly chat with the soon-to-be-late Tarsus Beetle. It's not completely clear when he first appears, as the initial batch of Jägers being more anonymous than the later crew, but he's first named .
He's fairly generic as Jägers go, looking the same as most of the Baron's entourage (except for the blond Zudok) and really only differing from the majority of them in having a given name, and a broken nose. He sustains this during the episode at Clay Mechanical after Klaus and Gil track the Search Engine to there and draw some mistaken conclusions about Agatha "Clay" (not yet revealed as the heir to House Heterodyne) and Moloch von Zinzer. After the Search Engine made a move to protect Agatha, the three Jägers hoisted up a clank gun to try and subdue it. Such is the hardiness of the Jägers that Stosh only suffers a broken nose after being by the recoil.
Following this exchange, he fades back into Jägerisch anonymity and isn't seen again, but at least he gets one moment in the sun, or more accurately, the crankcase oil.
In Agatha H. and the Airship City, (pp. 74-79) the lower-ranking Jägers who assist Gil in moving Agatha, Moloch, and the remains of the clank out of Clay Mechanical are not named. Instead, there is an officer Günther. One or more of these low-ranking Jägers receive a blow to the face not from use of the clank gun but from Günther's efforts to silence them about how Clay Mechanical smells fonny and that the clank reactivated not from interfering with Moloch, but Agatha.