For mature readers (18+), this genre serves as a safe space to explore the fantasy of breaking social rules without real-world consequences. The "portable" nature allows for a private, guilt-free exploration of dark romantic anxiety.
Now, let's address the keyword:
To read the manga on your phone or tablet, you should use official digital platforms that support mobile browsers or apps: fuufu koukan modorenai yoru manga portable
No one mentioned the rules.