That's Xylene, the one who sent the omnitrix to earth; not Verdona, Ben's grandma. Fix the tags.

Side note, I'd pound Xylene too.

It's honestly impressive how the Ben 10 character designers were able to create something that was so radically alien yet was still feminine enough that you can instantly grasp why Grandpa Max could be physically attracted to her…

…without resorting to giving her giant honkers. I mean she has enough curve in the chest region to hint that she might have A or B cups, but that's nothing compared to the massive DD's artists normally resort to when they want to give a creature that's obviously not-human sex appeal.

What I'm saying is that I appreciate the skill that made that restraint possible.