Story
Oreki Houtarou is a self-proclaimed "energy-saver" - that is, he will not actively waste energy doing things that aren't necessary. Though he had no interest whatsoever in joining any clubs upon entering Kamiyama High School, he was commanded by his older sister Tomoe to enter the school's Classics Club, which was in danger of getting abolished as all previous members have graduated.
Synopsis via AniList (English).
Preview
From the anime adaptation: Hyouka.