After Swapping Bodies With the Regent

I'm a puppet emperor, and I've always lived in the regent's shadow. Nobody takes me seriously. But after a beam fell on me during an ancestral sacrifice, my status began to soar, because... I became the regent! When I entered the palace late at night and saw the regent who had become me, I slowly broke into a smile. Heh, didn't see that coming, did you? Top, emperor is the top, younger partner. Theme: Communication is the best way to solve problems.