Soldier Bugs are a subspecies of Luck Locust used by the Tsukigata Fukoshi and are created by the Old Ones. Unlike Luck Locusts who can only steal luck and are incapable of fighting, Soldier Bugs are tools that can fight and steal the luck of others. A Soldier Bug will develop a bond with the Fukoshi it serves and shows enough intellect to understand human thought to a degree, such as Dahn asking his Taromaru to take his luck and make a luck crystal from it.
Jiromarus are used by the weaker Blask Masked Fukoshi, Taromarus by the higher up Red and Gold Mask Fukoshi, and Tentomaru by Lord Tento. Due to the Soldier Bugs useful ability of stealing their target's luck and having the ability to kill them, Lord Tento uses them as a bargaining chip to keep the village under their control. Taromarus are faced as random encounters in the Gold Fukoshi's Fukorutsubo.
Dahn planned on controlling the similar Apollyon insects to replace them, which ultimately fails.