Make the quick cherry syrup by combining cherry juice and simple syrup in a medium saucepan over medium heat. Stir until warmed and slightly reduced, about 5 minutes. Remove from heat and let cool.

Muddle 1/4 cup maraschino cherries in a mixing glass or bowl using a muddler or back of a spoon.

In a pitcher, combine the cooled cherry syrup, cranberry juice (if using), and lime juice. Stir to combine and taste; adjust sweetness or tartness if necessary.

Add chilled sparkling water to the pitcher just before serving and stir gently.

Assemble individual glasses by placing ice, spooning muddled cherries, and pouring the mocktail mixture over the ice.

Garnish with lime slices and rosemary sprigs.

For final presentation, skewer a maraschino cherry and add fresh pomegranate arils if desired. Serve immediately.

Store leftover syrup in an airtight jar in the fridge for up to 7 days.

Clean any used glasses and utensils promptly to avoid sticky residue.