Masuo is Sazae's husband and works as a salaryman in the sales department at a trading company. He's 28 years old (32 in the manga version) and originally from Osaka.
His defining trait is being genuinely good-natured but also pretty timid—a combination that sometimes gets him played for a fool or put in awkward positions. He'll occasionally say or do things that come across as oddly selfish or underhanded, which catches people off guard. But underneath it all, his gentle and honest character has won over Sazae's whole family, and he seems genuinely content with his life surrounded by them day to day.
Content compiled by AnimeList.moe from publicly available sources.