I have a character in my story who openly identifies as part of the goth subculture. I've taken pains to make sure they have a three-dimensional personality and aspects to their character beyond just being "that goth". About the only stereotypical "goth" thing about them is that they're crabby and cynical, but their personality is understandable in-universe and part of that is character motifs of the individual having a thorny exterior appearance to match their personality.
However, I've been noticing a problem in that while the character openly says they're a goth, it never quite feels like I am depicting a goth. Their characterization just feels shallow and undeveloped compared to many of my other characters, specifically because I don't know how to handle their gothiness. There don't seem to be many resources as to how goth subculture works or advice on how to depict it in fiction. I get that goth subculture is defined by individual expression so its pretty hard to pin down, yet there are still some clear dos and don't to differentiate it from, say, emo.
Adding to this is the fact that the character is not white (specifically, they're Native American in a modern setting), so it's really hard to figure out how gothiness interacts with culture. For example, I know many goths favor ostentatious jewelry, but many native traditions frown on wearing too much jewelry outside of formal occasions. I know that Native American goths exist (I've seen writings from several on how they get fed up how Native characters are typically only brought up in a Wild West context), but I don't know any personally to ask how goth and native traditions intersect. I've tried reading about the actual traditions and beliefs of the nation they belong to, though said nation hasn't actually written about a lot of them.
Because goth subculture is a common character archetype that shows up in fiction, I thought it would be a worthwhile question to ask here. How do I go about depicting a goth character and actually make them feel like they are a goth, rather than a shallow depiction of goth subculture?