CIM means cum in mouth. It’s where you ejaculate into your partner's mouth. It is one of many wonderful ways to end a session.
We did a sexy survey with both men and women who like to receive a CIM and 95% said what their partner ate or drank beforehand contributed to the taste of the cum. Our advice is to make up your partners favourite desert and eat it before you want them to eat you.
As we always say communicate with your partner beforehand and make sure both or the three of ye are in agreement.