Its all of the above, its an honour, its humiliating, but its also paying respect to your wifes pussy and the bull, by consuming his seed, that after it has just pleasured your wife, as a cuck its also a show of respect and a symbolic thank you, by not letting one drop of his sperm go to waste. Unlike a cucks cum that usually gets thrown in the trash or flushed down the toilet, licking up a alphas cum, gives it a much higher status and shows it is prized and not to be wasted. Most alphas love seeing their cum being seen as such a treasured commodity.
You have an intense and awesome understanding of all of it. I love cleaning her pussy regardless, but it's so much better when the black bull is there to watch. I love the look of satisfaction and domination and superiority on his face, and I want to please him as much as I please my gf's pussy.