On July 10, 2024, shortly before the release of previous single "Woman's World", Perry teased "I'm His, He's Mine" on a social media livestream along with other songs off of 143.
[citation needed] Perry co-wrote "I'm His, He's Mine" with featured artist Doechii, as well as LunchMoney Lewis, Ferras, Ryan Ogren, Theron Thomas, and its producers Dr. Luke and Rocco Valdes.
[7][8][9] Chris DeVille of Stereogum described the song as "perfectly competent" but also being "tryhard energy" and "poisoned" and pointed the featured artist, Doechii, "can't save it.
Magazine reviewed the lyricism having "much substance as a baby's speech" and critiqued the use of the "Gypsy Woman" sample by saying "Crystal Waters doesn't deserve this", but described the Doechii feature as a "redeemable factor" and her bars as "clever".
[12] In more positive reviews, Alexa Camp of Slant Magazine described the song a "low-key slow burner" and "more on trend" than previous singles "Lifetimes" and "Woman's World".