I think i'm finally happy with his design now, it was surprisingly hard to do what i was envisioning for him lol
Sazha! (means soot)
(I have a hard time expressing myself even in my native language, so the english description will be pretty short too lol, sorry)
Sazha is a nurse and mainly a stoker in the furnace of a huge underwater ship city . Lives in a commune on the lower decks
Despite his somewhat menacing and rough appearance, he (usually) has no evil intentions and actually is really calm and well-meaning, even if he's a little too straightforward and unperdictable when it comes to getting stuff done. He's pretty lonely, but dreams of finding true love and visiting the theater on the upper floors of the city. (He's actually really passionate about love stories and comedies, and watches a lot of silent films when he has some spare time (which isn't often) He also genuinely likes clowns. )
Extremely high pain tolerance (which is common for the people down there unfortunately), really tall and surpsingy strong for his complexion. Has a prosthetic second spine and a built-in hearing aid in his skull plate. Mute, rarely even uses the sign language. Sometimes carves trinkets out of wood or other junk just to keep himself busy

Setting is a huge submarine\underwater ship the size of a city. On the upper floors the standard of living is a bit better and people are less sick and poor than on the lower floors, but in general everyone there is so-so, because the ship is being powered by radiocative ore and pretty much everything still sucks for everybody. Most of the land outside is flooded or uninhabitable. If other people live somewhere on land, then also on some kind of constructed islands. The level of development, etc. is similar to the very early 20th century, but of course with a bunch of my unrealistic bullshit ideas. Industrial horror yadda yadda