In the world of Femdom, you will find many sets of rules, but they all seem to include cum-eating.
The problem for men is that, immediately after orgasm, they don't feel like it.
I suggest that - if you are even thinking about a femdom relationship, you will need to eat your cum at some stage. This is an essential submissive task, so learn it.
It is true that you can learn it by starting with a drop, the gentle way, but a mote affecting way it to make a major commitment to yourself, and JUST DO IT!
Collect your load in a suitable vessel, ideally one that can be licked properly, all over. Eat it as soon as possible after orgasm, and also learn to eat it cold.
Bear in mind that, if/when you are under femdom control, you might be orgasming once a month with eating demanded, so learn it now!