It is both interesting and important to understand that sexual expression encompasses a broad range of behaviors, both for humans as well as other living beings. What is acceptable varies over time and across cultures; some states still have laws on their books stating that sodomy (oral or anal intercourse) and is considered illegal (although arguably hard to enforce). These laws and enforcement change regularly. Investigate this topic (library, google, google scholar, etc.).
Share what you find on the laws of the different states to see what is illegal/legal and how recently some laws have been changed to eliminate illegal behaviors that are commonly practiced.