If and Only If, There Is and Only

Some time ago, I was preparing to write a science fiction book, but unexpectedly, I was busy with many things, and I stopped writing it at the end of the year. Just in spring, my friend came to ask me to write some stories and send some romances. I was thinking that writing romance and the like was not my specialty, more than that I was stupid, so I didn't respond. This is probably the reason why I designed the chapters to be short. I am not willing to spend too much time and ink on repeatable common situations. For example, the title "If and Only If, There and Only" was originally used in some rigorous mathematical axioms and propositions. Here it is used as the only, sufficient and necessary meaning, that is, someone asked me why I wrote it. Here is the explanation: Just like the title, they are all technical terms (chapter names) in mathematics, so they have nothing to do with it? But because of this, I feel that "irrelevance" is an absolute. Why can't people be related? Romance is the most straightforward way to reveal a kind of "relevance" between "irrelevance" and "relevance", so I began to feel the need to write something. This novel is my first or last romance novel.