Friends
The Idolmaster Cinderella Girls Starlight Stage Guide
In this screen, you can manage your Friends List, Friend Requests, Sent Friend Requests, leave comments, and search a specific player by ID. The number of friends you can have can be increased by ranking up through normal gameplay. If your friend list is full, you can't accept any new friends.
In the other hand, if another player's friend list is full and you accept his friend request, you still won't be able to add him/her. You can leave a comment to any of your friends in your list and you can also delete them deliberately
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