What does rain stick do? I checked the wiki and it said it affects night sequence but i cant see the change.
Yeah, there's info missing apparently, so basically if it rains during the evening, kaede appears in Yuna room at night, if you successfully convinced her to stay for sleepover at the end of the Friday party
There's a chance for the rain to appear at night, by using rain stick in the morning you make that chance 100%
Cheers