I (25F) am getting fed up with my boyfriend (27M) not being a munch!

I ‘25F’ want my boyfriend ‘27M’ to be a munch. But, I don’t think he will do it. We’ve been together 4 almost 5 years. I make “jokes” about him doing it but he always brushes me off and laughs. But, I’m not laughing anymore, I’m starting to get irritated that In the 4 years he’s never done it. I thought he would eventually try but, it hasn’t happened at all. I like that type of thing but, he’s doesn’t/hasn’t tried it I’m assuming. But, he’s talking about marrying me but he won’t do that & I can’t get married to someone who won’t be a munch. I like to feel good just as much as the next person! How can I bring this up without it seeming like I’m pushing him to do something?