Dice the tuna into small pieces, place in a glass bowl, cover with the lime juice and coconut milk. Cover and refrigerate for 4 hours. Pour off the excess liquid , and toss with 1 tablespoon of the olive oil and salt and pepper to taste. In another bowl, combine the mango, peppers, cilantro, shallots, coconut, and the remaining olive oil, and season. Combine remaining ingredients for relish. Begin building your parfait. Place 1 tablespoon of the relish in the bottom of each glass. Top with 2 tablespoons of the tuna. Continue until the glasses are full ending with the relish on top. Chill for 1 hour. Garnish with more cilantro sprigs.