What is in the egg you get in Pokemon Black 2?

In Pokémon Black 2, the egg you receive from the Day Care Man on Route 3 typically contains a Togepi. However, the egg can also be a random Pokémon based on the Pokémon you have in the Day Care. Players can hatch the egg by walking a certain number of steps, and once hatched, it will reveal the Pokémon inside.