We have had sex once before some weeks ago, without any of us finishing. Never found it to make any difference. Lots of factors can come into play, and not all of them are within someone's control. Sad fact is that plus size girls can't hit all the positions that skinny girls can and some things just won't work. Body worship can arouse both partners. Curves are fluid, meaning when her body moves they move with her. Thick is the new thin.
This makes for an all-round fun sexual experience, because you're able to let go and just have fun!
Science Explains Why Thick Girls Have Better Sex
Only thing you can do is experiment and see what you two wind up really liking. Why are chubby girls better in bed? My girlfriend is a little on the heavier side, at 5'8 she's not even big by my standards. It makes little difference except that when she's chubby, her vagina feels extra cushy. Joking or not, asking for pictures, hitting on people, etc, are not welcome here.