The 30-year-old musician took to Instagram on Sunday, Feb. 14 to share a carousel of images and footage of the pair together.
In his caption, he claimed that he wears Megan's blood around his neck. Sure enough, one of the pics featured a vial that appeared to contain a drop of blood and was hanging from a necklace. (See, we meant it literally when we called his post "heartfelt.")
"i wear your blood around my neck," he wrote, adding emojis that symbolize a knife, a drop of blood, a DNA symbol and a rose. "my bloody valentine."
On the same day, Megan also shared a carousel to her Instagram of video and photos featuring the couple in honor of Valentine's Day.
"there goes my heart," she wrote, "manifest outside of my body draped in the towering silhouette of a most unusually handsome boy magical and haunted kinetic and tortured ethereal and dangerous cosmic lawless eternal creative genius."
The 34-year-old Teenage Mutant Ninja Turtles actress continued, "the journey will likely be perilous but there is no destination without him happy valentine's day rehab barbie."
Included in her carousel was footage of Megan holding onto his waist from behind him while she had her feet on top of his as he walked her around the room. Machine Gun Kelly, whose real name is Colson Baker, shared this video to his Instagram Story.
Additionally, one of the pics Megan posted showed the "My Ex's Best Friend" rapper licking her pursed lips.
As fans recall, Angelina Jolie and Billy Bob Thornton famously wore vials of each other's blood around their necks during their short-lived marriage in the early 2000s.