Coco is the head witch of the town. She is the first character you meet, aside from the mirror, Cane. After you have found all key items in the treehouse, she appears, when you try to leave the house.
She loves Sera Berry Juice.
You will find her on the first floor of the Witches Guild.
First Quest: Bring her a Bramble Shroom
Second Quest: Bring her Super Slime
Third Quest: Bring her an Old Boot