Like you said, you're writing stories about people. So by nature, romance would have to come up. At least in glimpses. I mean, why else are Romantic Comedies so popular? Heck, even the staple characters that belong to my fictional universe of comics, who are fruit ninjas by the way not even human, enter the world of romance. In fact, there are relationships within my comics that have been set in stone already. To my final point, if relationships are brought up at all, and aim to be fully fleshed out, it should suit the creator to explore all stages of it including sex, marriage, breakups, casual flings, long-term flings, will they/won't they relationships, etc.