Sakuya is cosplaying as Boa Hancock from One Piece. The "Pirate Empress" (「海賊女帝」 "Kaizoku Jotei") Boa Hancock (ボア・ハンコック Boa Hankokku) is a woman of extraordinary beauty, the sole female member of The Seven Warlords of the Sea, captain of the all-female Kuja Pirates (九蛇海賊団 Kuja Kaizokudan), and ruler of Amazon Lily (アマゾン・リリー Amazon Rirī), an island populated solely by women.ch.516 She believes that because she is so beautiful anything bad that she does will be forgiven by everyone, and because of that she is not afraid to hurt pirates, Marines and even her own people. During their childhood, she and her two sisters were sold as slaves to the Celestial Dragons (天竜人 Tenryūbito), who forced them to eat devil fruits. She and her sisters still bear the brand of the Celestial Dragons on their backs. To conceal their shameful past from their kinswomen the sisters concocted a story about having defeated a gorgon, claiming that their strange abilities were the result of the Gorgon's Curse and that they have cursed eyes on their backs that would turn anyone who sees them into stone.ch.517,521 Hancock consumed the Love-Love Fruit (メロメロの実 Mero Mero no Mi) which gave her the ability to turn anyone charmed by her into stone.ch.516,521 Eventually, she falls in love with Luffy because of his selflessness and helps him infiltrate into the prison Impel Down to rescue his brother Ace.ch.522 Hancock also participated in the war, and she has drawn suspicion from some of the other marine officials due to her secret help to Luffy. Hancock also decreed that Luffy should recover on Amazon Lily to hide from the World Government. Her animal theme is the snake. Hancock is voiced by Kotono Mitsuishi in the Japanese version of the anime.
Her younger sisters both ate a model of the Snake-Snake Fruit (ヘビヘビの実 Hebi Hebi no Mi). The middle sister, Boa Sandersonia (ボア・サンダーソニア Boa Sandāsonia), ate the anaconda model. The youngest sister, Boa Marigold (ボア・マリーゴールド Boa Marīgōrudo) ate the cobra model. These fruits' abilities allow them to turn into a snake or a snake-human hybrid of their respective models.