Joushi Tono Hitoban

From Shinmakoku Scanlations:

Kondou Takayuki hates his boss from the bottom of his heart!! Takagi Toshinobu is mean, heartless, cruel, insensitive... a true sadist! And only to Kondou, by the way! He's perfectly nice to everyone else... WHY? Kondou keeps asking himself over and over again... Then one morning he finds himself in the same bed as his boss. Uwaah... What had happened the night before?