The Last of Us... Can be branched out into a sequel, but it can't repeat the same characters. The game itself is called "The Last of Us", it's a game about the last people who are struggling to survive in this post-apocalyptic society. And in the end, the game will tell the story of the Last of Us. It would define who is still left standing in this crazed society. Everyone got a taste of what it's like for a father to lose all, as well as a teenager who lost her identity as a kid. However other stories still could be told like a mother's story, a baby growing up in this violent society, etc. This franchise can grow in a huge way, and could therefore continue telling other stories.