“I produced it out in Japan, and I wanted to make a record that has that international type feel to it,” Charlie tells People.com. “Selena came on to it, and it completed it all.
“I’m good friends with her now, and we talked about wanting to collaborate, and I was finishing the song, and I was like, ‘Wouldn’t it be cool if you sang the second verse?’ And that’s really how it happened.
“She came over; she recorded it. I didn’t even have a studio set up; she recorded it in my closet, and it really added a lot to the record.”
It seems Selena’s tumultuous love life, including a highly-publicised on-off romance with Justin Bieber, was also a factor in her agreeing to lend her vocals to the song.
“I met up with Selena,” Charlie recalled to MTV News. “And she went through a very public relationship, on and off, and she could just relate to the song and the lyrical sentiment.
“I was playing the song for her, and she just started singing the second verse. I got chills. I was like, ‘Oh my gosh, that sounds so real. You need to sing on it.’ And she said yes.”