せじにうとい
世事に疎い inexperienced unrealistic knowing but little of the world

せじにくらい
世事に暗い know little of the world

せじょう
施錠 locking 世上 the world 世情 the ways of the world human nature

せじん
世人 the people the public the world

せじんをおどろかす
世人を驚かす to strike terror in peoples hearts