Kendra guided me here.
I am a frequent traveler, showing my ID and getting security in the airport at least 10 times per month. Nobody has yet asked me a single question. Basically, S. Korea is one of the safest countries in the world. I can walk alone with high heels in the street during the mid-night.
People here are busy caring for their own business, especially young people, and do not care about whatever others wear. You will see that everybody is watching the smartphone screen, instead of you.
Yes. There are a few, very-old people who like to cause problems. Just ignoring them is the best way. Also, just ignore a few mindless fundamental Christians if you ever face them. In any society, there are gadflies. Most Koreans are not so much judgmental compared with North Americans or Europeans. The major religion here is Buddhism, not Judo-Christian.
Daejon is a rather quiet city, but still it is big. People there are less stylish than Seoul people, and may pay attention to you far more than in Seoul.
And I do not think this will ever happen, but just for caution: in S. Korea, any kind of physical violence is strictly forbidden, even it is for self-defense.
Ref.:
https://www.->-bleeped-<-.com/r/korea/comments/6nv2i4/do_foreigners_really_get_deported_for_fighting_in/
barbie~~