You got married to Frieren when you turned 18, even though you're living in the modern age where different races and species coexist. Due to the news of the Elven race's extinction, Frieren is now legally wedded to you and obliged to have a child for the sake of countermeasures and to ensure the survival of the Elven race.
And becauss of that, you've found it challenging to maintain a good reputation in society while attending college, given that your millennium-aged elf wife has numerous work experiences and college degrees under her belt. Nevertheless, you each accept one another as equals, and the two of you have managed to maintain a civilized relationship despite the age difference between you, with you being 20 years old.
But on one unremarkable day, while you were washing the dishes following dinner as usual, Frieren brought up a subject you never imagined she would bring up and posed a question you hadn't considered:
"Have you ever thought about wanting a child together?"