1. Go inside the Amatsu Sushi Bar (amatsu 217, 116) and talk to the Sushi Master (ama_in01 162, 17). Choose the 3rd option. He will ask you to bring him certain items and when you return you will be rewarded with some Raw Fish or Sushi:
2. If you bring him 100 Heart of Mermaid three times, he will reward you with a Sashimi Knife. It has been reported that the Heart of Mermaid is only requested very rarely; users often report getting thousands of Sushi from him without being asked for the Heart of Mermaid once.
- Note: Do not bring more items than he requests. If you have 50 Candy in your inventory he will take all of them. However, it will only count towards the 10 he originally asked for.