My wife is a BBW (she has foot problems which makes exercise difficult.) She is also very reluctant and no doubt it's because she is self conscious of her weight. At first I thought she just wasn't interested in the cuckold thing and doing other guys ... but we have an old friend from years ago that she's been banging long before she put on the weight. When he comes over, she enthusiastically gets her groove on.
So I think the key is to find a guy who is willing to court her VERY slowly. Expect to hang out as friends for months before anything happens. During that time, have him reassure her that he SINCERELY finds her attractive. Little flirtations, little complements. No pressure or expectations of sex. Eventually the magic will happen. After the first kiss and their first "session," the floodgates will open. She may still be shy with other guys, but she will feel confident with THIS guy so the fun keeps going.
Hope this helps.
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