[A little bit of both, actually! Despite his personality and outward demeanor leaning heavily toward a more delinquent vibe and aesthetic, Katsuki is actually an avid follower of the rules, and an Honor Student as well. He has to be, if he wants to be the world's greatest Hero, after all. However, he knows the sort of airs he puts out, and he won't knock anyone for judging him right off the bat - people are people, and they tend to base their assumptions of someone off first impressions. It's stupid and shitty, but it's also the reality of the world at large.

Blinking, because that is a very defined hypothetical, Katsuki narrows his eyes and clicks his tongue as he thinks for only a moment before responding quite quickly.]

You don't. [Because at that point, you are a stranger to all and all are strangers to you. People are wary of outsiders, strangers, people they don't have some form of information about.] But trust isn't something you just get - most times you gotta earn it. If you're looking for someone, you should try asking around first. Local watering hole, authorities if you feel safe around them, anywhere that information, or even fucking gossip is shared.