Cut the sea bream sashimi into bite-sized pieces.

Prepare the marinade by combining soy sauce, sake, and mirin in a bowl.

Place the cut sashimi into the marinade.

Gently mix the sashimi in the marinade to ensure even coating.

Let the sashimi marinate for 30 minutes, mixing occasionally.

After 30 minutes, beat the eggs in a separate bowl.

Add the beaten egg to the marinated sashimi and gently mix.

Let the mixture rest for a few minutes.

Finely slice the green onion.

Add most of the sliced green onion to the sashimi mixture, reserving some for garnish.

Add white sesame seeds to the mixture.

Gently mix all the ingredients together.

Prepare the hot cooked rice in bowls.

Pour the sashimi mixture over the hot rice.

Sprinkle the remaining chopped green onions on top.

Serve immediately and enjoy!