Bathouses are about sex, my fellow Nebraskan.
Bathouses give the users a safe place to have sex, and do their drugs. That's what it is: no more; no less.
You need to be VERY CAREFUL as the folks there are often into multiple sexual partners, PER DAY, and often have drug, and esteem issues.
It's not where you'll find the best sorts of people, but, being from OMA, and young, you won't be any worse for the wear if you remember several things: if it secrets fluid, you need to be protected against it, be it a mouth, a dick, or an asshole. Don't touch a needle.
Bathhouses are an interesting social experiment for those folks without any sense of responsibility, foreplay, or acquaintance...basically 200 naked guys, most of whom are there for one thing, and one thing only: sex. It's a sad commentary on the human condition, but, it it what is it.
As a young man of 20, I think you should go check one out, just to see how low things can go: asses in the air; drugs everywhere; disease and bad practice abound. Bath houses are for the most self-indulgent of the self-indulgent, basically.