Venus the Plant Girl
This is Venus the Plant Girl, a green humanoid with powers similar to Poison Ivy or Groot. She used to be a beloved superhero once, but after a terrible secret came to light, she fell from grace and was exiled inside a distant dome away from the rest of society. Now, decades later, Yolk-Man is forced to break her out so the two of them can stop an even bigger plant threat.
She can come across as gentle and childlike, but there’s also something cold and raw about her at times. Venus puts nature first, and that often leaves her struggling to fully understand human behavior. She is deeply misunderstood, partly because her gentler happy side makes people underestimate her, while her colder feral side makes them fear her. She's as mystical as she is deadly.
Think Poison Ivy meets Björk meets Hannibal Lecter.