While the pair have only been dating for a few months, the seriousness can be seen through the photo and caption.
Last week, a source revealed to E! News that they are absolutely "inseparable", already taking a huge step in their relationship.
"They've become inseparable and Evan is staying with Halsey at her house," the source shared. "He still has an apartment in the valley, but she has a gorgeous new house that she bought last year. It makes more sense for them to be at her place, so they have been spending all of their time there."
"They seem very happy together," the source added. "They don't want to be apart."
We are obsessed.
Prior to Halsey, Evan Peters was famously dating his American Horror Story co-star Emma Roberts on and off for many years. At one point, they were even engaged.
As for Halsey, she was previously with singer YungBlud after a longer relationship with rapper G-Eazy.