If a Diclonius vector penetrates or even so much as touches a human male body, the "vector virus" is transferred to the human, causing their children to be born as Diclonii (when born from humans, they are called "Silpelits"). An incident involving the escape of a child Diclonius during Kurama's early years, where the Diclonius' vectors penetrated him without causing him pain, resulted in Mariko being born a Diclonius and Kurama taking precautions against a recurrence by urging Bando to be sterilized. All Diclonii (Silpelits) born from human parents are sterile and female. There is only one Diclonius that is actually capable of reproducing: Lucy, the "queen".