In a mixing bowl, whisk together olive oil, melted unsalted butter, minced garlic, paprika, and Cajun seasoning until fully combined. Add lemon juice, kosher salt, and black pepper.

Toss shrimp into the marinade, ensuring they're completely coated. Cover and marinate in the refrigerator for 15 to 20 minutes.

Preheat your grill to medium-high heat, about 375-400°F. Allow the grill pan to heat for about 5 minutes.

Thread marinated shrimp onto skewers, leaving a little space between each.

Place shrimp skewers on the grill and cook for 2 to 3 minutes on each side until pink and opaque.

Brush remaining melted butter over the shrimp while cooking for added richness.

Remove grilled shrimp from skewers, transfer to a platter, garnish with parsley, and serve with lemon slices.