Where found: On the first day, talk to Anju while wearing Kafei's Mask between 2 and 7 p.m. - she'll set up an 11:30 p.m. meeting. Return to the inn at night using either the Deku Flower outside or the room key and head to the kitchen. Talk to Anju and she'll give you a letter. Drop it in one of the mailboxes and wait until the second day, then you can visit Kafei in his room by the laundry pool once the letter has been delivered.

    How helped: After you speak to him, return to Anju and give her Kafei's pendant so she'll wait. On the final day, go to Ikana Canyon and head right from the broken bridge until you reach Sakon's hideout. If you allowed the old lady from the bomb shop to be robbed on the first day, then Kafei will have spotted the thief and be hiding behind the rocks - join him and wait/warp to night (6 p.m.) of the final day.

    Stay out of view and wait as Sakon opens the door to his hideout, then run in and navigate the puzzle. You'll alternate between Kafei and Link; push blocks onto the blue switches as the former and kill enemies quickly as the latter. Succeed and you'll save the Sun Mask, so return to Anju's room at the inn and wait until Kafei arrives. Watch the scene and you'll receive the Couple's Mask.