Donburi container Black & red

Donburi or donburi mono containers (food in a bowl) are very common in Japanese restaurants.
It is usually filled with white rice, plain or seasoned, and then covered with raw or cooked fish simmered in a sauce, simmered meat with sauce, soft-boiled egg, raw vegetables, shrimp, grilled eel with lacquer...
The contents can be hot or cold. The lid keeps the heat in.