According to Rowling , to characters for whom wizarding blood purity matters , Lily would be considered `` as loathsome as a Muggle '' , and derogatively referred to as a `` Mudblood '' . According to Rowling , to characters for whom wizarding blood purity matters , Lily would be considered `` as ` bad ' as a Muggle , '' and derogatively referred to as a `` Mudblood '' .