Railway safety. On airplanes there will sometimes be people who clap when the plane lands safely. In modern cars we have a number of safety features that are pretty hard to ignore. But with trains everyone is (rightfully) focused on punctuality. Only in the rare event of a crash or similar so most people even begin to think about the safety aspect.
First off: if, then he wouldn’t be a pedophile but a hebephile. Small, but important difference.
Second: there are the laws. If you’re breaking laws, it could quickly become a problem (obviously).
But finally, what you were actually getting to: it really depends. There are plenty of age cases that are unacceptable no matter what (e.g. if he were 25 instead of 19, for instance). People mature differently. I’ve met people who were 16 where you could think they were 20, and vice-versa. If one is much more mature than the other, than you have a power imbalance, and that’s the problem. And that can happen with two people of the same age, as well (although it’s less likely).
So, no, 16 and 19 isn’t necessarily wrong, per se. The question is: is the relationship in question problematic?
I’ll keep it short: no, there is no “healthy” amount of dandruff. Definitely look beyond the 3-in-1 combos, those can really make things worse. And if that doesn’t work, ask a doctor, since dandruff can have a number of different causes.
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