2AM's Seulong gave a sneak peek of his upcoming duet track "Female Friend" featuring Lovelyz' Kei on 'Knowing Brothers'.

On the June 13th episode, Seulong featured as guest, and though Kei couldn't join him, Cherry B. filled in for her during a short live of the song. In the clip above, the 2AM member reveals a preview of his upcoming release that's described as a romantic, light-hearted tune perfect for summer. 

Seulong's "Female Friend" featuring Kei drops on June 16 KST. Check out the MV teaser here if you missed it, and watch the sneak peek above!