Most people will think of the words sexy, innocent, and cutie when they are in a girl group. However, an unusual girl group has challenged in the K-pop scene.

They are the four-member girl group High School.

High Schoolhas been covering their face with a mask even before their debut, has released their second digital album "Baby you're Mine" on April 30.

"Baby you're Mine," is now released and it is the second album following the first single "Pre-Single High Class."Given that the first "High Class" is an event album for high school’s fandom, the second album is officially debuting.

The controversy over the mask of high school is currently ongoing.The public still feels unfamiliar withtheir character, as there are no examples of girl groups hiding their looks, not sure about whether they can sing in masks or when they will not reveal their faces.

Attention is focusing on the move of "High School"