The Brief: A "stock market bf" is a boyfriend who invests in and is interested in the stock market.

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The “stock market bf” trope is often paired with an “astrology gf” or an “OnlyFans gf.” Stereotypically, a stock market boyfriend is a boyfriend who is interested in the stock market as a hobby or career. He may also be a finance bro.
The term rose to popularity alongside discourse around StonkGate: when individual investors from the subreddit r/WallStreetBets caused the price of GameStop stock to surge.
where’s my stock market bf
— traitor joe (@phoebe_bridgers) January 29, 2021
astrology gf stock market bf
— golf daddy (@foulweathered) January 27, 2021
Stock market bf and astrology gf pic.twitter.com/hnzi0nvGEl
— Nabil Shamim🕷 (@twatson_13) January 28, 2021