I believe you but Jean here is sitting on his lap, drinking bear, talking about being too good for each other and tastes of poison, Logan's running his hand through her hair and they are alone as well.And we've seen them kiss on panel in Wolverine as well.I think it's pretty clear what happened here.
Aside from the comics explanation below, there is also some other stuff
Yeah, we have to keep in mind comics don't show nsfw stuff a lot of the time and I think them kissing in pretty clear in the last panel.