Krin Kasim is the central protagonist of the anime Fang of the Sun Dougram. He is the son of Donan Cashim, the governor of the colony planet Deloyer, who initially came to power through an election but later declared martial law and established an absolute dictatorship supported by the Earth Federation. Because of his father’s political connections, Krin receives training from the Federation ace Jacky Zaltsev in piloting the standard Soltic H8 Roundfacer combat armor. When a coup by Colonel Von Stein appears to threaten his father’s rule, Krin takes up a Roundfacer and fights alongside Federation forces, only to discover that his father secretly collaborated with Von Stein to consolidate power. The revelation of this duplicity and the regime’s violent suppression of the independence movement leave Krin stunned and disillusioned. Following a meeting with Dr. David Samalin, who introduces him to a prototype combat armor he has designed, the Dougram, Krin and a group of companions form the rebel cell called the Fang of the Sun. They join the growing resistance against the Federation-backed dictatorship with the goal of ending the governor’s tyranny and securing Deloyer’s independence.

Throughout the series Krin develops from a sheltered young man whose advantages derive from his father’s position into a dedicated guerrilla leader. His motivations are forged by a sense of justice and personal responsibility after witnessing his father’s betrayal and the suffering of the colony’s population. Key relationships define his journey: an adversarial dynamic with his father Donan, a complex relationship with his former mentor Zaltsev now on the opposing side, and close bonds with his fellow fighters in the Fang of the Sun, including the scientist Samalin. His abilities as a combat armor pilot are a central asset; having been trained on the Federation’s standard Roundfacer, he adapts quickly to the more advanced and unconventional Dougram, using it in numerous surgical strikes against occupation forces. Krin’s growth is marked by his shift from privileged bystander to committed insurgent, as he channels his training and moral awakening into a protracted guerrilla campaign against the regime he was born into.