Successfully complete the indicated task to unlock the corresponding character icon at the saved game screen:

Beat: Successfully complete the third week.
Joshua: Successfully complete the second week.
Mr. Hanekoma: Collect all secret reports.
Mr. Mew: Get 100% Pin Mastery.
Rhyme: Collect all items.
Rhyme (noise form): Successfully complete the noise list.
Shiki: Successfully complete the first week.