May 13
Would any of your OCs have scars in their stomachs? 
Do stomach's scar on the inside?
(Pause for quick Google search)
Yeah, yeah they do. I assumed they probably would if ulcers are a thing.
Some of my pred characters definitely earned a good cut or scrape at some point (eating live, unwilling prey comes with its risks), but I think poor Lou takes the prize for literally getting cut open once upon a time. He got better, but the evidence of his biggest blunder is still there, inside and out.
Captain Leviathan probably has some scuffed up innards as well from their years of eating rebellious prey...and Levi's unfortunate habit of gulping down opponents without completely disarming them. Thank Dagon for their tough stomach lining...