I have a married guy I service regularly with oral, usually through a glory hole while he views straight porn. His wife will not blow him, so I satisfy his need, no reciprocity of any kind.
Since I am providing a service to please him, we often discuss via email the details of what he wants, how it can be better. I express that I will do whatever he wants, and he isn't shy about asking!
He has never asked to see his cum in my mouth. He loves enthusiastic desire for his cock and cum. He likes having me feverishly sucking as he climaxes while my hands grip and stroke his shaft. He is big enough for hands and mouth at the same time!
In our discussions he loves the fact he is feeding me, that his cum is enjoyed, savored, and cherished. Often it is my breakfast and his cum is actually providing my body its first nourishment of the day.
I usually have to swallow as he is still pumping because his loads are big and i don't want to have any overflow... i want every drop! I milk his shaft with my hand at the end and lick up every drop I can coax out , and lick his cock clean.
Again, he loves that his cum is taken with such enthusiasm. He also likes the superiority of his position of being the bigger hung man having a servant worshipping his nice big cock. I always praise his size! He leaves very happy knowing his cock providing me pleasure by serving him.