Series of short stories revolving around a poor builder and a wealthy proprieter, including Sweet Prison and a non-related side story: Northmen

Ch01 - 4-Jouhan Sweet Home: Mizuho is living on the verge of poverty in a 4.5 tatami mats room (7.3square meters) due to his family’s debt. One day, he collapsed from hunger and was carried home by his unruly coworker, Yae-san. Is the willful Yae truly what he appears?
Ch02 - Sweet Prisoner: A misunderstanding leads to S&M.
Ch03 - Sweet Worker
Ch04 - Sweet Memories
Ch05 - Northmen: Takes place in the time of the Vikings.