Songfacts®:

• This song is about jealousy and insecurity, that unfortunate feedback loop when you start doubting yourself and worry that your significant other has someone on the side.
  
  Michelle Zauner, who spearheads the Japanese Breakfast project, wrote the song in 2013, inspired by her budding romance with Peter Bradley, who plays guitar and piano in her band. "I was really in what they call the 'friend zone,'" she told Drowned In Sound. "When we started dating each other I felt like he wasn't attracted to me. I felt so jealous and ugly and insecure."
  
  She needn't have worried: Bradley was into her, and in 2014 they got married. "In retrospect what really happened, I just imagined this whole affair, this flirtation, and blew it up in my mind," she added. "It was so rooted in my own feelings of ugliness and jealousy."
• Zauner released the first version of this song in 2013 on a cassette she made called June with one song recorded every day of that month. A year later she recorded it with her punk band Little Big League, who released it on their second (and last) album, Tropical Jinx. That band broke up in 2014, so Zauner focused her creative energy on Japanese Breakfast while holding down a job in sales. The first Japanese Breakfast album was released in 2016 and earned her a record deal with Dead Oceans. She recorded the song again in 2017 for the next Japanese Breakfast album, Soft Sounds from Another Planet. The album made inroads in the indie pop realm but it was the third album, Jubilee in 2021, that grew the fanbase considerably. That year, Japanese Breakfast earned a Grammy nomination for Best New Artist.
• Zauner worked with her producer Craig Hendrix to create a lush soundscape for the track in the style of '60s ballads by Roy Orbison and Phil Spector productions from that timeframe, which meant lots of layers to tap into the melancholy of the lyric.
• Michelle Zauner directed the music video, which she describes as a "space prom." It was shot at Richboro Junior High in Bucks County, Pennsylvania, where Peter Bradley, who inspired the song, went to school. Many of the extras in the prom scenes volunteered after Zauner posted the call on her Instagram.
• "Boyish" is one of the more enduring Japanese Breakfast songs. It usually shows up in the setlists and continues to do well on streaming services.