Meaning
穴子 (あなご, Anago) is Saltwater eel, a Japanese food (water animals).
What is Saltwater eel?
Anago means "salt-water eel", normally referring to ma-anago ( Conger myriaster ). They are often simmered for sushi or deep-fried as tempura , compared to unagi (freshwater eels), which are usually barbecued with a sauce as kabayaki . Anago is also slightly less rich and oily than unagi, and has a very soft texture and sweet taste.