There is a species that is quite sentient. Its members know about the world, they have hopes and dreams and great aspirations of what they might do with their lives. They are intelligent, creative, caring, empathetic and deeply feeling individuals. However, this particular species bears a heavy curse. The male partner dies less than one day after mating. This is not the result of ritual, cannibalization or necessity, but a reaction of their biology itself.
They (assuming they are told or they figure it out) realize what fate holds for those that partake. The female partner shall live, while the male shall perish. Sadly, there is no guarantee that their sacrifice will result in a child, nor do they have any way to stop the impending death when it is set in motion. But the question is, would they make the sacrifice, knowing full well the consequences and risk?
There are a few more stipulations:
- Males can only potentially impregnate one female.
- Males will live a normal, full length life, if they do not partake (Barring disease or accident).
- There is no way to artificially inseminate or otherwise avoid natural reproduction in the case of furthering the species.
- Females that are able to bear children are likely to bear more than just one; between two and four. More than four is rare and zero is uncommon, but both cases have been documented.
- There are no documented cases of successful childbirth after one or both parents have lived beyond 1/3 of their lifespan.
- Diseases the parents have are likely to transfer to offspring. Only healthy individuals are recommended. Though uncommon, healthy children sometimes come from unhealthy parents.
So, can this species persist? How would a culture form regarding the two genders? Would society pressure individuals to reproduce, despite the cost of life? What other unforeseen implications would this have?
Note: I've seen a few people concerned about child birth mortality rates in pre-medicine times. You can safely assume that majority of pregnancies have consistently had minimal mortality rates, even during the darkest of times. At the highest child deaths throughout history have only occurred at about 1:10000 children (a tradeoff for killing off one of the parents perhaps), and that number goes down significantly with technology and medicine.