Tatsumi gives off a kind, generous, level-headed and friendly vibe. He was shown to be a bit arrogant and naive in the early chapters, when in his first appearance he believed he could be given an immediate rank of Captain in the armed forces. He displays a great displeasure of killing, unless provoked as shown from finding his friends tortured to death. He shows great admiration for Bulat, though he doesn't agree to Bulat's displays of affection. Overall, he displays great comradeship and great promise of being a skilled fighter. Close to the start of the manga, his affection spreads even to his enemies, giving him a liability. However, with experience, he has learned to show affection for his friends, but none to his enemies. He is capable of great rage when provoked by his enemies, making him a formidable opponent.