It depends on the Bull and the situation.
My first experience was not a friendly relationship with the bull as he essentially stepped in and took my place when my girlfriend and I were having difficulties. When she decided to continue dating him after we got back together things progressed to the point that she was openly cuckolding me in so far as her family and our friends knew about it. Fortunately, what she didn't make public were the things I had to do to make her agree to not leave me, even though I eventually decided to call it quits.
However, he always made sure I knew who was the "top dog" and would lord his position over me as far as he could, occasionally making my girl feel sorry for me and tell him to back off a little. Which is all he would ever do, back off just enough to appease her.
The second time was a more cordial relationship where the Bull and I got along well and shared many common interests as well as the same woman. So, even though I was subservient to him and he was clearly dominant, we got along well and he never abused his position over me or really mistreated me. Occasionally, if it was "girls night out", he and I would get together and go have a beer or two and play pool at a local bar.
Yes, even with the second one it could be a bit awkward at times, especially taking his phone calls to let my then fiancee know when he would be coming over or calling him for her.
Probably the most uncomfortable conversations were those when we would be at the bar or sitting around the apartment and he would become antsy waiting for her to return and start talking about how he couldn't wait for her to get back home so he could fuck her tight pussy, what a great cocksucker she was, did I really enjoy eating her pussy after he fucked her and things of that nature.