According to Mystic Entertainment, "Hara featured in Thunder's new song. Not only are the labels [of the two singers] close but Hara happily decided to feature after listening to Thunder's song which she said is really great." 

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The upcoming album will be Thunder's first music promotions since his departure from MBLAQ and also his 1st solo album since debut. The full release is set for December 7.  

Make sure to check out Thunder's new release featuring Hara!