Is the relationship 100 reward being able to wake up Yuna or is the reward just the cutscene?
Wait wait, let's clarify some things - if you have relationship 100 the game let's you wake her up during the night and continue having fun with her, as far as I know, you will still see gaining credits afterwards in the bottom corner of the screen, but after you end the night you should get 0 credits, cuz technically waking her up is treated as "game over", but since you have rel 100, your reward is a morning event scene and being able to fuck her with her eyes open.
Is this how it's going, or after needing the night you get credits?