This Boss Is Too Conscientious

The protagonist traveled to this parallel time and space. Because the technology in this time and space was underdeveloped and there were no things like air conditioners and washing machines, the protagonist invented them. When they were first invented, people laughed at them. Later, they became surprised and shocked. They never imagined that this long thing could be so cool. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.