I might not be the first one to point this little detail out from what 
Brendan said, so please be kind:

... I guess that the Kunos are one of the noble famlies that has been 
marrying its sisters for a while, and as a result the all have a very 
tenuous grip on reality, and a tendancy to obsess even more than what 
is considered normal in the Ranma universe.

Doesn't this scream sick/ridiculous/lemony/downright-insane plotline/idea/
fanfic to you?

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