Stir everything together in a small pitcher until the agave is dissolved. Pour into a glass filed with ice, and garnish with a lime slice and some pomegranate arils.
Notes
If you don't have the time or energy to make fresh pomegranate juice (see instructions in post, above), look for fresh juice at farmers markets, or use a flash pasteurized variety that contains only pomegranate, such as Evolution brand, carried at Whole Foods.Use a decent-quality gold tequila here, such as Patron or Cazadores.The quantities of lime juice and agave will vary with the sweet/tartness of your pomegranate juice, so start with the amounts listed and add more as needed to balance flavors.Nutritional values are based on one drink.