"Put molly all in her champagne, she ain't even know it. I took her home and I enjoyed that, she ain't even know it," say the lyrics to the song, which was released in February.
"Molly" is slang for the psychoactive drug MDMA or ecstasy.
CNN said scores of protesters picketed outside a Reebok store in New York Thursday, demanding the sportswear manufacturer boot Ross as a celebrity spokesman.
"We are asking Reebok to drop their endorsement deal with Rick Ross," Shawna Thompson, a spokeswoman for the women's rights group that led the demonstration, told CNN. "The reason we are asking them to do is because Rick Ross recently rapped, bragging essentially, about drugging and raping women. We see this as an opportunity to elevate the fact that it's not OK to do that, and he shouldn't benefit from endorsement deals when he has rap lyrics like that."
"I dont condone rape," Ross said via Twitter. "Apologies for the #lyric interpreted as rape. #BOSS"
After his apology was criticized as being insincere, Ross tweeted: "Apologies to my many business partners, who would never promote violence against women. @ReebokClassics @ultraviolet"
CNN said Ross and Reebok's corporate headquarters did not respond to requests for comment on its story.