File:Sieanna Todoroki.jpg

Sieanna Todoroki (轟焦凍, Todoroki Sieanna), also known as Sienna (シエ, Sienna), is the older twin sister of Shouto Todoroki.

She is a student in Class 1- A at U.A. High School, where she got through official recommendations and is training to be a Pro Hero. She is the youngest daughter of Endeavor, the No.1 ( formerly No.2) Hero.