While there is scarce material on Blanche Dumas, her alleged lover Juan Baptista dos Santos was the subject of some fairly intense study.

Juan Baptista dos Santos was born in Portugal around 1843 in the town of Faro and was examined for the first time when he was only six months old. His parents and two siblings were well formed and it was said that his gestation and birth were uneventful. As a child, Juan was considered quite handsome, fit and well proportioned – except for the two distinct genitalia and extra fused limbs he possessed.

It was observed that urination proceeded simultaneously from both penises. What appeared to be a third leg dangling from the pubis was in fact two limbs fused together as one with a small and supernumerary anus. The compound limb had a patella but, while the limb joint was freely movable, it had no motor control or power of motion. A journal, published in London states that Juan Baptista dos Santos had been exhibited in Paris, and that the surgeons advised operation.

That operation never occurred as a further report from Havana, dated July, 1865, details a further detailed examination of Santos at twenty-two years of age. This report also brought forward the claim that Santos possessed an ‘animal passion’ and had a ravenous sexual appetite and permissive reputation. This same report claims that Juan Baptista dos Santos used both penises during intercourse and, after finishing with one he would continue with the other.

A further report details the physiology of Santos in full adulthood and is accompanied by a detailed illustration. This report also detailed Santos was in the habit of wearing this limb in a special sling or bound firmly to his right thigh. This not only prevented the limb from dangling, it also allowed him greater freedom of activity – he was said to be an avid horseback rider.

During his lifetime, Santos was perused by several sideshows and circuses. In 1865 – he turned down a contract worth 200,000 francs to perform in a French circus. However, Santos opted to exhibit himself to medical authorities and rare ‘special’ exhibitions. Despite his extensive medical examinations and relative fame in medial circles only one photo of Juan Baptista dos Santos and that to focuses mainly on his dual genitalia.