The Conglomeration Effect
The year is 2096. The earth has seen two more world wars since 2016. The last war that destroyed a quarter of Canada and half of Japan, was enough to make the government enforce strict actions.
Countries are now split, no communication at all between them. Humans now live in conglomerations of small pods stacked upon each other. Each person has their own space, but they're all confined to being underground. Half of the people living inside the pods have never seen natural sunlight.
Birth rates are violently controlled due to the lack of space and pods constantly having to be built. Couples are allowed, but physical contact reaching past anything more than a hug is forbidden. Sex is strictly banned unless it is agreed by contract or an operation is done to assure a baby cannot be created.
It's a tough life. It's a boring life. And it's a lonely one too.
A life underground simply isn't good enough for some.