Songfacts®:

• Machine Gun Kelly first met actress Megan Fox while filming Midnight In The Switchgrass. They immediately connected and started dating before announcing their engagement on January 12, 2022. Kelly concludes his Mainstream Sellout album with this ode to his twin flame.
• It's been six days since the last time I saw your face and you asked my sign
  I told you mine, I question why, and you said, "Everything's aligned"
  On the first day, you told me, "I was your twin flame from a past life"
  And tonight the moon is full, so take me anywhere outside
  
  Being someone's twin flame is a more intense form of being their soulmate. Fox knew right away Kelly was her twin flame. "We're actually two halves of the same soul, I think," she said during the couple's first joint interview on Lala Kent and Randall Emmett's podcast, Give Them Lala. "And I said that to him almost immediately, because I felt it right away."
  
  "I think it was the second day [of filming]," Fox added. "I asked him to come into my trailer for lunch, and I put him through all of this astrology stuff. I went deep right away."
• The interlude of the pop-punk ballad features a private recording between Kelly and Fox.
  
  I feel like, I'm just leaving here and...
  You feel like what?
  Me and you can just drive somewhere, we can just leave
  Okay, I love you
  I love you
  In this film I know, there's no happy ending
  In this film I know, there's no happy endings
  
  "In this film I know, there's no happy ending" is also the chorus of Mainstream Sellout's opening track, "Born With Horns," which MGK sings as a proud outcast. By closing the record with an ode to finding love he does find a happy ending.
• Mainstream Sellout is Kelly's second collaborative project with drummer and producer Travis Barker, following 2020's Tickets to My Downfall. They wrote "Twin Flames" with MGK's regular collaborator Nick "Dark Waves" Long, Los Angeles producer Omer Fedi, the singer's keyboardist and bassist Steve "BazeXX" Basil, and his hype man Brandon "SlimXX" Allen.
• Machine Gun Kelly performed "Twin Flame" at the 2022 Billboard Music Awards on May 15, 2022. He introduced the ballad by saying, "I wrote this song for my wife," suggesting he and Megan Fox had tied the knot.
  
  During the song, MGK interjected, "This is for our unborn child," prompting speculation about a lost pregnancy for the couple.
  
  "Broke my heart to sing the end of that song," Kelly later wrote on Twitter. "I recorded 'Twin Flame' two years ago today, the second half came a year later. Beautifully serendipitous getting to sing it for you tonight."
• Around the 2:50 mark, there appears to be the sound of a heartbeat hidden in the pop-punk ballad. So who does the heartbeat belong to? Kelly was cryptic during an Instagram Live session. "I was actually wondering if anyone would pick up on, so I'm going to plead the Fifth on that one and just let you guys have that to guess what it is," he said. "That's a rough one to talk about."
  
  Want more songs containing a heartbeat? Check out 16 Songs With a Heartbeat.