Metsubou Sekai de Aku no Kagakusha to Ai wo Hagukumanai to Ikenai you desu

The Earth was destroyed by a giant meteorite and the only humans left behind were the "evil scientist" Noir and the "Saint Warrior" Mirei, enemies who once fought over the Earth. As Mirei tries to carry out justice in a desperate situation, Noir suggests, "Let's create a new planet by having children". While Mirei tries to decline the enemy's unexpected suggestion, it doesn't seem to be that bad altogether...?