My Husbands weird fantasises

Hi I’m a 33 year old and my husband is 37 years old. He has a very weird fantasy of making out with multiple women. Its disgusting for him to even think about this, he has been bothering me on this from quite some time. In just a joke I said okay once and from there on he is after me, he is saying I should approach my friend and she would be comfortable, else he say he will go to Thailand or somewhere, There he could hire 1 or 2 more girls along with me and want this life dream to be fulfilled. I said please don’t of me doing this, if you really want, goahead yourself and do whatever you wish to in Thailand. I’m not comfortable at all. All these thoughts have damaged me emotionally. I don’t feel like sleeping next to him but he is the father of my kids and he is overall a nice person. I don’t know how do I make him understand his fantasies are weird and impossible.