Mao Onigawara

Mao is the girl with pink hair who defends Japan from the ground by using a tank (the tank was officially named 'White Tiger,' but she refers to it as 'Mee-kun' for reasons unknown). As revealed in assorted Physical Education scenes, she is a very slow runner. Also, going by a statement she makes during the sports fest, she has no mother. Her clover pin is green.

Read more at http://myanimelist.net/character/6611/Mao_Onigawara#JSUwUqmQOMylP21e.99