gekota

Gekota is a popular mascot found in merchandise marketed to children in the Toaru Majutsu no Index universe. Misaka Mikoto is a huge fan of the franchise it belongs to, which - much to her consternation - gets her labeled as childish. Other Gekota fans (gekoers / ゲコラー) include Hokaze Junko and Iizumi Rita.

Its pink version is called pyonko.