So my wife and I have been together for 20 years and married for 16. She is great at giving oral sex,(and recieving) however she will only ever get me almost there and then stop and climb on. I really want for her to allow me to finish and then kiss me with my cum still in her mouth. We have talked about it but she has some sort of mental block to me finishing in her mouth. How can I maybe convince her of the excitement this would give me?