Divide sushi rice into 8 portions and shape each portion into an oval with hands moistened in vinegar water. Cut octopus meat in 8 flat slices and sprinkle with lime juice. Let stand for 5 minutes, then pat dry and spread each slice on one side with a little wasabi. Lay rice portions on the coated octopus slices, pressing gently with left thumb tip up against the rice so that it retains its shape. Turn the nigiri sushi over and reshape with two fingers..

Cut the nori into 8 strips. Wrap 1 nori strip around each octopus nigiri. Slightly moisten the ends and press into the underside of the nigiri. Serve nigiri sushi with the rice side down.