In what year was the album “Cushion” released by SONAMOO?

In what year was the album “Cushion” released by SONAMOO?: The album “Cushion” was released in 2015 by SONAMOO, featuring 6 tracks.
What is the most successful song from the album “Cushion” by SONAMOO?: “Cushion” is the biggest hit from the album “Cushion” by SONAMOO.

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