I think if I'd just stumbled on this, I'd assume it was a cover painting. Not just because of your incredible artistic skill - and your skill is indeed incredible - but because it so perfectly captures these characters. I'm not a regular reader of these comics, but it seems very likely to me that these two were indeed paired at some point. (Certainly Swamp Thing is allowed to join a Poison Ivy led team in the Batman Miniatures Game, and they tend to be moderately catholic about only allowing pairings justified by the stories.) Very well done, ser!
Thank You.....someone else asked me in another forum if they ever did team up, so I did a search and found they actually did....but from what I saw looked like only teamup, nothing romantic