Yes,it's a collaboration.

Yes,it's between South Korean singer and American singer.

Didn't expected it,huh?

FYI,the guy that was singing with is named Jeon Jungkook. Stage name: Jungkook. Yes,he's Korean and can sing English.

Here's a full cover:

https://www.youtube.com/watch?v=UNvb6qP26J4

And here's the duet with the other member:

https://www.youtube.com/watch?v=RbctNBlXBJc