Here’s an excellent example of physical intimacy for a cuckold couple as well as a very clear demonstration of roles. According to the poster of this video, she had denied him orgasm for six weeks (not recommended for prostate health), but puts this video into perspective.
This level of teasing and denial takes considerable practice and training. His wife obviously knows her boy’s penis very well and can precisely read his level of arousal and risk for spurting. It’s not uncommon for husbands to cry from the level of frustration endured during such an experience.