Glamorous unapproachability

I've been conducting reserach into Mills and Boon - for my novel - (one character is a romantic novelist) - and came across the theory of glamorous unapproachability - which is the idea of male characters who are attractive but there is some impediment that stops the heroine getting close to them - they are not confined to Mills and Boon by any means - Darcy and Mr Rochester both spring to mind.