Just about anyone, it would seem. The main trains I ride are Chicago’s CTA and DC’s Metro, which both attract quite a diverse crowd. I think people see me as a good seatmate because I am small and quiet and mostly stare out the window. The only time I seem to be singled out is when tourists get on the Metro and want to ask a question; they often look to me probably because I look both harmless and like I know what I’m doing.
I always have headphones on and am intently staring at my screen. As a result I mostly get either people who don’t want to be disturbed or those who plan to talk loudly enough on their phones that I must restrain myself from beating them with whatever weapon is handy.
I try and sit in the two-seat benches at the end of trains so I don’t get squished by strangers on both sides, so I usually attract people with asses which spread themselves over to gently push me into the bulkhead. Sometimes it’s also skinny guys who spread their knees so wide you check to see if they have elephantisis, or little kids because I look trustworthy.
Any females, or people in pairs/groups, but only younger males. I’m short and small and have a young face, so older men probably think they’ll scare me?