Yoon Ji Sung reveals notes in 'Dear Diary' teaser image

Red Velvet's Yeri smiles for the camera in 'Dear Diary' MV teaser for 'SM Station'

Red Velvet's Yeri sits on a garden swing in 'Dear Diary' teaser image for 'SM Station 3'

'SM Station' reveals making of Red Velvet Yeri's upcoming 'Dear Diary' MV