Koushiki Furin

Fumiya, an office worker in his seventh year of marriage, is troubled by his sex life with his wife. Though he loves her dearly, his own body fails to respond during intimacy. With no children and constant pressure from their relatives, the couple suffers daily. Then, one day, they are suddenly torn apart by the government and forced into cohabitation with "new partners." This is state-sanctioned infidelity, carried out under the guise of countermeasures against the declining birthrate!

(Source: Kodansha, translated)