In a Boston shaker, muddle pomegranate seeds with agave nectar to release the juices.
Add Arrogante Blanco tequila, a high quality grenadine (by Stirrings, Sonoma or Jack Rudy), Aperol (Italian aperitif with a complex bitter-sweet taste derived from the infusion of many herbs and roots) and freshly squeezed lime juice. Top off with a handful of ice and shake vigorously for 15 to 20 seconds.
Strain the cocktail through a fine mesh strainer into a small wine glass or a champagne flute filled with fresh ice.
Garnish the drink with a slice of lime and several pomegranate seeds.