Origin

Cindy Shears was born with a gene that was similar to but legally distinct from the X-Gene. It was discovered by Dr. Kavita Rao when Cindy start exhibiting super strength. Rao was ready to investigate a cure, and Cindy's parents agreed to it. Cindy wanted nothing to do with it, so she ran away from home and never saw her parents again. She lived by taking jobs as a super-criminal while wearing her DIY pink rhino suit.

Creation

Rhinoceress debuts in Avengers Academy: Marvel's Voices Infinity Comic #4 by Anthony Oliveira and Bailie Rosenlund

Major Story Arcs

Sinister Six

After a run-in with cadets from the Avengers Academy, Squid Kid recruited Cindy for his new version of the Sinister Six. Their first action was to break into OsCorp and kidnap Stanley Osborn for the goblin formula written into his genetics. Some of the members of the Sinister Six were not into kidnapping a child, but Cindy just needed to be paid.

Stanley's brother, Normie, was a student at the Avengers Academy and talked his fellow cadets into recuing his brother. Fellow member, Mysteriant, worked with the cadets to set up an illusion to save Stanley and bankrupt Squid Kid. Without any money, Cindy split.

She started working at a queer-friendly bar, where she would cross paths with multiple students of the Avengers Academy, who aided her when she was targeted by a former employer, Klaw.