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If you can tell me if there was any dialogue at all I maybe able to answer. Specifically I think i can find it if there is no dialogue
That’s a bust
If you can narrow down some genres and content warnings (like human experimentation), then I can use an anime filter to find it
And what is a tat?
Here are male mute black haired characters, recognize any?
https://www.anime-planet.com/characters/all?hair_color_id=7&gender_id=1&include_tags=597
Scratch that not all mutes are labeled
What year do you think you saw it, and where did you watch it on
^^^^A tat is a tattoo, I believe. No idea what this is, though.
This popped up in head. I have no idea why but my friend and me are going crazy. There was anime short where a brother and sister escape like this prison thing and they had like matching special tats. They lived on a mountain side hiding away from them and the both of them never said a word. Both of them were mute. They lived high above the clouds and had this little hut thing that looked fururistc as well. The brother was trying really hard to protect his sister and it was really pretty looking ugh. Its stuck in my head but the picture of its stuck in my mind. They had orange outfits on and I think the girl had short black hair and other was older with a bit longer black hair.