Daisuke Niwa is the main protagonist of the manga and anime series D.N.Angel, created by Yuki Narumi. He is a 14-year-old boy who transforms into the legendary phantom thief Dark whenever he experiences romantic feelings. This transformation is tied to a family curse that has affected the males in his lineage. As Dark, Daisuke possesses exceptional agility and skills in thievery, often stealing valuable art pieces. However, he struggles with his dual identity, balancing his normal life with the responsibilities and challenges that come with being a thief. His character explores themes of love, identity, and self-acceptance.