Mirio Togata

Age: 18-
Gender: Male   

Height: 181 cm (5'11")
Occupation: Student
Affiliation: U.A. High School
Quirk: Permeation

He is third-year student at U.A. High School and is part of The Big 3 (the strongest three hero students in all of Japan). Before Izuku Midoriya, Mirio was the top candidate for All Might's successor and inheritor of One For All. His Quirk, Permeation, gives him the ability to become intangible, letting him pass through any tangible matter; he can phase through walls and/or the ground, as well as let enemy attacks pass through him harmlessly.

(Source: My Hero Academia Wikia)