How to Advance in the Game

So I finished the first miracle outfit and learned about the second one, but there's been no more main quests for days. Are there prerequisites? Why aren't they listed anywhere if so? What am I supposed to do next?

So I finished the first miracle outfit and learned about the second one, but there's been no more main quests for days. Are there prerequisites? Why aren't they listed anywhere if so? What am I supposed to do next?