Tigerlily (named Zuruko in the original Japanese version) is Yuna's mean, bullying cousin who appears mid-way through Season 2 of Stitch!
Role in the series
Although she is harsh to Yuna, she claims she's only trying to be a role-model. Because of this, she blackmails Yuna into doing the chores around the house, because of her bad grades. Yuna and Stitch reluctantly move off to live with her in Season 3 and she starts to mellow out a bit.
Though she treats Yuna the way she is, Tigerlily (like Nani towards Lilo) loves and cares about her cousin deeply, nevertheless, and would do anything to keep her out of danger, even if that meant sacrificing something of her own. But she will use them another way to get Yuna to do what she wants as repayment.