"Souvenir" is about the thrill of an affair, which seems to reference a line from a song of Gomez's other famous ex, The Weeknd (Abel Tesfaye). Gomez sings, "You're giving me chills at a hundred degrees / it's better than pills how you put me to sleep / calling your name, the only language I can speak," which could be seen as a direct callback to The Weeknd's song "Call Out My Name." The song was featured on his infamous breakup EP My Dear Melancholy dropped in March 2018, after his breakup with Gomez in October 2017. It's been long assumed that the song (among others) was about Gomez, so it's only fair that she repay the favour, right?
Watch Selena Gomez's "Souvenir" lyric video above!