Not everyone reads the tags or comments so they are surprised. I wouldn't call it innocent btw, not everyone reads hardcore yaoi you know. And not liking pee sex is not being boring. You need to chill.
And, you know yaoi isn't innocent neither? If they started reading this, I doubt they were looking for a family story.
What I mean is that they shouldn't be surprised by just this, there are a lots of things more hard.
And of course, you don't have to like it... But God, people get crazy for everything. If you start reading something perverted, don't be surprised if you find perverted things on it.
If you're gonna get disgusted by the pee thing, why are you even reading this? Pee fetish is one of the most innocent things a yaoi could have xD (Even though I think he doesn't really have a fetish, It's more like he is up for anything if it involves his boyfriend)
Everyone complains like if it was so serious, ¿Can you be more boring?