
I feel gross after reading the sister chapter, but then I remembered that we're basically doing the same thing she is, we're just not in that universe...

incorrect! She is watching people in real life (at least in her fictional universe) without their consent having sex, which is a huge invasion of privacy and just messed up. What are we doing? We're reading fictional yaoi manga. Its not real for us, they are fictional characters, without any ego.
For her, she is actually watching real people have sex. For us, we are reading about fictional characters having sex. Can you not distinguish the difference??

but that contradicts your statement that we are basically doing the same thing as her in the same way hence why you said "I feel gross after reading the sister chapter, but then I remembered..." suggesting that it would be simply hypocritical to critisize her actions. Correct me if i'm misunderstanding sorry!

The sister was watching them have sex, which is creepy, especially because she is his sister. I then realized that we're also watching (reading?) them have sex and if you think about it we're pretty much doing what his sister is doing. I was simply making a comparison between her actions and ours as readers. It looks like my phrasing was too confusing since more than one person interpreted my comment in a different way.
My boy is never gonna be able to shit the same way ever again.