Wanna Thompson, 26, has long considered herself a Nicki Minaj fan.

As a freelance writer living in Toronto, Ms. Thompson also counts herself as a cultural critic with a focus on hip-hop, and with her insights, she has built an audience via her personal website and social media feeds. So when she posted a tweet one evening late last month about Ms. Minaj’s recent musical direction, Ms. Thompson hoped only to spark a conversation among the rap obsessives with whom she regularly communes.

“You know how dope it would be if Nicki put out mature content?” Ms. Thompson wrote to her then 14,000 or so followers. “No silly” stuff, she added with an expletive. “Just reflecting on past relationships, being a boss, hardships, etc. She’s touching 40 soon, a new direction is needed.”

What happened next was one part dystopian sci-fi, and one part an everyday occurrence in pop-culture circles online: The Nicki Minaj stans — or superfans — attacked. Then, galvanizing them further, Ms. Minaj chimed in, too.

In the week since publicizing the acidic messages she received directly from Ms. Minaj, whose next album, “Queen,” is scheduled for release in August, Ms. Thompson said she has received thousands of vicious, derogatory missives across Twitter, Instagram, Facebook, email and even her personal cellphone, calling her every variation of stupid and ugly, or worse. Some of the anonymous horde included pictures Ms. Thompson once posted on Instagram of her 4-year-old daughter, while others told her to kill herself. Ms. Thompson also lost her internship at an entertainment blog in the chaotic days that followed, and she is now considering seeing a therapist.