My wife is actually somewhat muscular just naturally, and could be a lot bigger than me if she wanted to (her traps are breath-takingly large) but she is self conscious of it and as a result doesn't like to flaunt it. Like most women, she is naturally submissive in the bedroom but she does entertain my submissive fantasies/kinks occasionally. Having said that, when we are doing the normal love making, I definitely fantasize about things - whether it's fantasizing about her dominating me, or drawing on my past with other women who were much larger (some bodybuilders, and others like Amazon Amanda, Blythe, Amazon Ashley, etc.) completely overwhelming and humiliating me. I also fantasize about what it would be like if one of these women were to dominate me while my wife watches. That remains my biggest, and to date, most elusive fantasy.