In a small bowl, finely dice the red onion and cover it with the juice of one lime. Allow the onion to soak in the lime juice for about 10 to 15 minutes.

After 10 to 15 minutes, whisk in 2 tablespoons of olive oil with the now-infused onion and lime juice. Set aside.

In a large mixing bowl, cut the watermelon into bite-sized pieces. Add the chopped fresh mint and parsley.

Gently fold the marinated onion mixture into the watermelon. Add Kalamata olives.

Top with crumbled feta cheese and season with freshly ground pepper to taste.