There are simple T-shirt bras and lacy lingerie. Silky slips and nursing bras. Shapewear, strapless, corsets, bathing suits. The sizes run from the smallest smalls all the way up to a 46M. For items that are mostly meant to be hidden by clothing, underwear comes in a wide selection. But at Iris Lingerie in Boerum Hill, Brooklyn, customers rarely paw through the racks of unmentionables. Instead, women put themselves in the capable hands of Iris Clarke.