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Sorry I didn’t know it was legal(or pleasant based on sanitary reasons-see my original comment) to have sex in a public bathroom. I don’t understand what u mean: based on ur diction u seem to think that it is rational perhaps even necessary (by an arbitrary force that makes it a law of nature) to stop everything and have sex. Obviously this is a yaoi so of course it is. I just wanted to show my sympathizing thoughts to the comment that seemed to express their “exasperation” [not in a too serious way tho] at this common yaoi trope. Clearly I didn’t expect so much badgering and based on this I guess i gave u some level of distress and for that I am sorry. (Plz stop answering back in unnecessary ways that do not add any substance to the discussion and also see borderline rude). Sorry if mine came of that way(rude i mean) but I was answering literally and as sincerely as i could
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Teenagers, young adults (around university age) and even certain adults (depending on circumstances) don't have a lot of options of places where they can have sex.
A lot of Japanese people tend to live with their family for their entire lives. Partly due to filial piety and partly due to convenience (location, money, etc). And you don't just bring your casual hookups home - that's usually reserved for very serious, we're getting married types of relationships. Why do you think love hotels are so popular in Japan and not in the west? Here, we don't need hotels that charge per hour because most adults have their own apartment/houses.
One thing you'll notice if you ever visit Japan is that there are few teenagers working - compared to the US where the majority of service jobs are done by teens. That's because a lot of high schools won't allow students to have part time jobs. Only extenuating circumstances like the student being from a single parent, low income household would allow the student to get permission to have a part-time job. Or students are only allowed to have temporary part-time jobs during winter/summer breaks. So teenagers have limited ways to earn money.
Young adults and adults may have more options to make money but when you're young and horny, I can see why all you can think to do is find the closest place with four walls. Plus, don't forget that LGBTQ+ have even fewer options than horny hets.
Anyways this is just my observations. I'm sure toilet sex being so common in yaoi/hentai (I don't know about josei since I don't read a lot of that) is an exaggeration but based on some truth. I'm not Japanese so maybe I'm missing some other info but if I think of it this way, it makes sense why toilet sex shows up a lot.
Ok but why a bathroom again?!