Isami Tahara is the NPC created by Akira Oono (Kunai, Hakuto) of the series Maou-sama, Retry!. A man whom Kunai Hakuto called genius when he summoned him. He is a top tier soldier at heart, and has a lot of experience leading people. His wide range of weapons make him extremely challenging opponent against anyone who dares stand in his way. Tahara is usually teasing people with a smirk on his face, and his attitude is the very definition of lack of energy. His ability to provoke people is also uselessly high. It feels like he has a lax expression, but at the same time it is a poker face, and for the enemy, he is a character that is hard to grasp. Tahara has a little sister far younger than him, and the setting is that he entered the committee and does the dirty work to earn the money for his sister’s upbringing. He is a good person at heart, but he shows no mercy to enemies at all. By the way, he has a serious case of siscon, practically a disease. He categorizes women as 'Manami' and 'the others', so he has reached a summit where even doctors would throw the towel. His presence is highly reassuring for Kunai, since he knows that with Tahara being there he doesnt need to worry about security.
(Source: Maou-sama, Retry! Wiki)