Ishilly has three freckles on each cheek and long black hair, which she has braided together with golden hair clips. Furthermore, she has decorated her hair with small red flowers. Around her neck she wears two necklaces. Matching her striped fin she wears a striped bikini in the same colors.
With the other mermaids, she gave a friendly greeting to Luffy, Sanji, Usopp, and Chopper when they came accompanied by Camie. However, when the Neptune army showed up, the mermaids quickly tried to hide their new friends. While doing so, Ishilly pressed Sanji against her bosom to keep him quiet. However, Sanji was pouring so much blood from his nose due to this situation that it was already becoming dangerous for the ship’s cook.
Later, Ishilly and some other mermaids opened a found barrel, from which Caribou emerged. The latter used his devilish powers and captured the mermaids.
After the Straw Hat Pirates defeated Hody Jones, all the missing mermaids reappeared. From the looks of it, Caribou had to release them again so that he would have room to escape from the palace with the treasures. This allowed Ishilly and the other mermaids to join the Straw Hat Pirates for the banquet.
- Ishilly is one of the superstars among the dancers at the Mermaid Cafe, along with Kairen, Hiramera, Seira and Mello.