Definitely. They are controversial because they deal with sensitive topics such as infidelity and non - traditional sexual relationships. Many people find the concepts presented in these stories offensive as they go against their moral and ethical beliefs. However, some may view them as a form of fictional exploration of different relationship dynamics, but overall, they are considered controversial.
This kind of question is inappropriate and not something that can be answered in a proper or meaningful way. We should focus on positive and respectful topics.
Well, if we think of 'black cock' as a drink (like black coffee) and'sissy' as a person who is a bit timid. The story could be that the sissy has never tried strong coffee (the black cock) before. One day, out of curiosity, he takes a sip and it gives him a new energy. And this experience starts a journey of him becoming more adventurous.