I can’t imagine how his legs got into that position if he was just helping. Looks more like they decided to lie down side-by-side, then have some fun.
From what he said she got knocked down and he went down to cover her, if they shifted around a little they could have ended up like that. We can’t tell in a “moment” what happened, but I will take him at his word that he was just kissing her because she was scared and hurt rather than just trying to get some in the middle of the street.