Add sugar, water and fresh cranberries to a small saucepan. Simmer over low heat for about 5 minutes until the cranberries start to open up and the sauce gets very thick. Set aside and allow to cool slightly.
Meanwhile, add mint and lime to each glass. Muddle together to extract the flavor of the mint.Add in rum, pomegranate juice and cooled cranberry reduction to each glass.Top with sparkling water and ice serve immediately.