Theresa, known as Tsuburi in the original Japanese version, leads the streaked shearwaters. A traumatic event in which the antagonistic weasel clan under Noroi slaughtered all her subordinates, spouses, and eggs serves as a primary motivation for her actions. She forms an alliance with the group of protagonist mice, uniting against the common enemy to defend the island's inhabitants from the invading weasel forces. In the English-language adaptation, the character's gender differs from the original Japanese depiction.