Rinse the octopus under cold water. In a large pot, bring water to a boil, adding celery, a halved lemon, bay leaf, peppercorns, and salt. Submerge the octopus, dipping the tentacles in and out of the boiling water. Cook for 40-45 minutes until tender, then carefully remove and let cool.

Once the octopus is cool enough to handle, slice it into bite-sized pieces and set aside in a large mixing bowl.

In a separate pot, bring water to a gentle simmer and add the halved lemon, tangerine, bay leaves, and a pinch of salt. Gently drop in the squid and tiger shrimp, poaching for about 2 minutes until fully cooked. Drain and set aside with the octopus.

In a medium bowl, whisk together olive oil, tangerine juice, lemon juice, minced garlic, honey Dijon mustard, and a sprinkle of salt.

In the large mixing bowl with octopus, add poached squid, shrimp, and any remaining juices. Drizzle dressing over seafood mixture and gently toss until well-coated.

Transfer the seafood salad to a serving platter. Garnish with freshly chopped parsley.

Serve salad at room temperature or refrigerate briefly to enhance flavor mingling.