Bleach
So Hichigo/Shirosaki/Zangetsu is depressed.
Like...
Ichigo was scared of him and he secretly just wants Ichigo to like him because they're two halves of a whole and Hichigo just wanted to be heard and seen but Ichigo dislikes him just because of what he is and it hurts.
The Old Man gets annoyed with him sometimes too and Hichigo has no one.
So he slowly and subtly gets quieter and starts appearing less until they barely see or hear him anymore, and they don't realize it because he did it slowly and subtly.
Then Ichigo calls on the hollow mask during a fight and it appears and after the fight Ichigo realizes he hadn't heard his hollow once and then he realizes he hasn't heard from his hollow in a while so he go to his inner world to look for his hollow but he can't because Hichigo hid himself really well.
Cue frantic search for Hichigo throughout the inner world.
Meanwhile Hichigo is taking refuge in a relatively dry building from the flood in Ichigo's mind and he's napping.
The idea dwindles here.
Then they find Hichigo and conflict arises and they talk it out before Hichigo becomes more happy.
The idea ends here.