Oshamanbe is a recurring antagonist in the anime Nanako SOS and an original character created for the television adaptation. He is a mad scientist who lives in Hokkaido and commands a group of followers known as the Hokkaido Main Line Group. His overriding ambition is world conquest, and he seeks to use Nanako's superpowers to achieve it, which leads him to repeatedly target her throughout the series. His appearance reflects his Hokkaido roots: he wears a bear hide and is frequently seen eating corn, and he travels in a submarine shaped like a bear. Within the story he functions as one of several rival scientists who oppose Yotsuya, each competing to obtain Nanako's abilities for their own schemes. His personality is that of an ambitious and self-serving inventor whose plans consistently put him at odds with the main characters. The episodes treat him as a comic-style villain, and the series does not show him changing or developing beyond his fixed role as a schemer. His prominent strengths lie in his scientific inventiveness, represented by his bear-shaped submarine, and in the organizational control he exerts over his subordinates, while no individual superhuman powers of his own are portrayed. His key relationships are defined by his rivalry with the scientist Tomoshige Yotsuya and by his ongoing efforts to capture Nanako, whom he views purely as a means to advance his goal of world conquest.