Rinse the cleaned octopus under cold water and place it in a large pot. Add chopped celery, a halved lemon, bay leaf, peppercorns, an optional wine cork, and salt. Cover with water and bring to a boil over medium heat, then reduce to a simmer. Cook for 40-45 minutes, until the octopus is tender.

In a separate pot, fill with water and add the juice of one lemon, a tangerine, bay leaves, and salt to taste. Bring to a rolling boil over medium-high heat. Add the cleaned squid tubes and poach for 2 minutes, then add the peeled and deveined tiger shrimp and cook for 2-3 minutes until pink and opaque.

Prepare the dressing by mixing 1/4 cup of olive oil, the juice of the tangerine, and the juice of the remaining lemon in a jar or bowl. Add minced garlic, honey Dijon mustard, chopped parsley, and salt to taste. Whisk until well combined and emulsified.

Combine the octopus, shrimp, and squid with diced celery in a large mixing bowl. Drizzle the homemade citrus dressing over the seafood mixture and gently toss until everything is evenly coated.

Transfer the seafood salad to a serving platter or bowl. Garnish with additional chopped parsley if desired. Let it rest for about 10 minutes at room temperature before serving.