This is a very generic question without details. What is your desired relationship? What is his current maximum willingness to commit? Are you looking for a full heterosexual exclusive-marriage-with-children version? Is he only willing to be friends-vs-tricks (i.e. friends without benefits), or casual-and-open (which may vary from totally open to don't-ask-don't-tell), or 5-year-plan (get more serious if neither has found an alternative)?  Are there other differences, such as leather-vs-vanilla? You may never achieve a full exclusive relationship. 

So, with your heart-to-heart, determine what degree of intimacy / exclusivity is available. Then determine whether it is something that you can accept / work with. There is no point in trying to be exclusive if that happens only on a one-way basis.