This figure, labeled Amititia (Amicitia) in the lower left, represents Friendship. Juan del Castillo took the elements of the allegory from Cesare Ripa's Iconologia of the 1600s, which became a standard reference work for artists searching for ways to represent abstract ideas. According to Ripa, Amicitia was to be shown as a fair young woman, simply draped in the white robe of Truth, the virtue upon which friendship is based. She goes barefoot "for friendship knows no inconvenience too great for it," and rests one foot on a skull, "for friendship jeers at death." The artist probably intended the sphere drawn here as a free allusion to the skull. The inscription cerca (close) and lexos (far) on her breast refers to Ripa's description of keeping friends close to one's heart, regardless of whether they are near or far.
Castillo drew a study for a scene of Christ on the Cross on the back of this drawing. Since Castillo drew the cross at an oblique angle, the figure may have been made for a Raising of the Cross.