This is a Japanese-style bento lunch box for carrying food in. It has two tiers, each with their own lid, and a final lid to go on top.

Have you seen cute bento boxes filled with rice balls and rabbit-shaped boiled eggs and sushi? These are great for taking a cold lunch and keeping various parts of the lunch separate. When you are done, the middle tray nests inside the bottom tray for compact storage. You can even put some small chopsticks or silverware in the top.

The lids may need some support material; everything else can just be printed as-is. I think PLA is fairly food safe, but you should probably hand-wash and not microwave it.

There's a FreeCAD .fcstd file with all the parts included, and stl files for each individual piece. If you wanted to, you could add an relief of your favorite SVG image to the lid to make it very personal.

You'll probably want a band to keep it together; if you sew a piece of 1" wide elastic into a loop that should work pretty well.

UPDATE: Changed the divider to make it a little bit smaller. Also updated the boxes and lids to have a little more clearance.