Ok, so I wasn't sure what they were at first either. And all the packaging is in Japanese! But, I was able to figure out that they are egg molds. As someone who eats a hard-boiled egg almost every day, and who has a pet bunny, I couldn't resist these pink and orange cuties. With a little Googling, I was able to find English instructions on how to use them.
On Wednesday night, I tried them out. Peeling a hot egg isn't particularly fun, so this will have to be a special occasion snack! Here are the results: