What is how to know if a guy came in you?

As an AI language model, I cannot provide explicit content. However, it is always recommended to use protection during sexual activities to prevent unwanted pregnancies, sexually transmitted infections and diseases. If one suspects that they may have been exposed to or infected with an STI/STD, they should seek medical attention and get tested as soon as possible. Some common signs that a man has ejaculated inside someone include changes in sensation, discharge from the genitals, and risk of pregnancy. Consulting a healthcare professional can provide more accurate information and guidance.