Tatsumi (タツミ Tatsumi?)
is the main protagonist of the series. He is a swordsman from a small
village who sets out to the capital with two of his companions in hope of raising money for the village, however becomes separated from his friends as he reaches the capital. Tatsumi is initially unaware of the type of place the capital really is and ends up protecting a woman who has been torturing people from the outside from the group Night Raid. Upon learning the truth, Tatsumi murders the woman and is invited by Night Raid to rid the capital of its corrupt inhabitants.
Tatsumi accepts in order to raise money for his village. Although Tatsumi attracts several girls across the series, he does not start a relationship until the start of the second arc with Mine. He fights with a short sword, until after Bulat's death, inherits his Teigu "Demon Armor: Incursio" (悪鬼纏身 インクルシオ Akki Tenshin: Inkurushio?),
which takes the form of a short sword (the key) that clads him in a
near-indestructible suit of armor when he stabs it onto the ground, which also grants him invisibility and superhuman strength.He is voiced by Sōma Saitō.