People that walk with a funny “swag” and wear “chav” clothing. I immediately presume they are the lowest of the low and put my hands in my pockets to protect my valuables..
I’m going to say this, then sound like a hypocrite, but, tattoos. I have a full sleeve, and 8 others. All can be covered with trousers and a shirt. But when I see people with tattoos on there knuckles, and neck / face, my “scum-alert” senses go wild.