Silent Towns
Summary A war broke on Earth, and everyone starts leaving Mars to go visit their families, to see if they are ok. Absolutely everyone leaves Mars, but two people, they meet. He was the last man on Mars, and she was the last girl in Mars, but he didn't even think about marrying her because he just didn't like her much, so he escapes and lives alone for the rest of his life. There is another man who claims to be the last man on Mars, and build robots to act like they are his family, because his "real" family dies. After some time, some families go back to Mars to escape the war and be "safe".