Quickly Clear up the Article, Don't Give Birth to a Child, Don't Want a Scumbag to Whitewash the Article, Please Be Normal

There is a small world where the female protagonist travels through time and becomes a man. I remember there was a plot where the male protagonist went to find the female protagonist (the female protagonist dressed as a boy) and went to a place like a slum. The female protagonist's status in the small world was very pitiful.