Lu Chen transmigrated to the Great Sum Dynasty, becoming the Ninth Prince of the dynasty. Unlike the transmigrators in novels, Lu Chen didn't have extensive engineering knowledge, nor did he remember much classical poetry. In order to avoid getting involved in the succession struggle, Lu Chen could only lie low, planning to enjoy a quiet life of splendor and wealth. Due to his mother's status, Lu Chen was eventually granted a marriage by the Emperor and was assigned to be Prince over a bitterly cold territory in the north. Just when Lu Chen thought he was going to decay in such a manner for the rest of his life, he activated a system on his wedding night. As long as he sired a heir, Lu Chen would be able to receive rewards and even enhance his own power. Years later. Lu Chen marched into the capital with a million-strong army to support the Emperor, and everyone was dumbfounded. "Wasn't this guy a useless Prince? Where did he get a million-strong army from!" "What's happening, how could he possibly be a Grandmaster?" "Turns out the Ninth Prince's decadence was all an act!" ...
The biggest sadness in this story is the protagonist's lack of will, if he were Chinese or Korean, perhaps he would take his training more seriously because in these two countries, unlike Japan, military presentation is mandatory, another sad factor is that only human wives had children , of course with the exception of Juna who is 25% Sea Serpent.