Zenmaijikake no Tina(1999)

Tina has fun every day on Zenmai (Coil) Island with her friends, Princess Frog, Pumpu and Shama. Then one day, after school, they come across an unconscious boy by the "Once Upon A Time Waterfall."

Unlike the other people and creatures who live on the island, the boy does not have a key on his back that needs winding. He can't remember anything about his past, and Tina pities the boy because she is all alone too. She makes friends with this mysterious boy.

On an island where people wind each other up to show love and affection, this strange outsider brings chaos to their peaceful lives.

Note:
Volume 2 includes the one shot "Koisuru Kokoro" (コイスルココロ)