[COMPLETE] This Is What Happens When a Stupid Father Learns "the Lifespan of His Unborn Child"

There was a crown prince who drank heavily and was absorbed in gambling, despite his wife being pregnant. Then, before this man, a person claiming to be the "incarnation of the Lord of the Underworld" appears――. ※ ・You should be able to finish reading in about 15 minutes. ・I take care to avoid them, but if you spot any typos or omissions, please feel free to point them out. ・It's a story about nobility, but the dialogue is modern in style.