I woulden't either. Anytime I see that meme pop up from friends... I automatically assume they don't like it. If not hate it outright. Why else would they post that? (Yes I know it may be because they kick or fight or whatever.) I also realized there was no point in bringing it up to them. I've already told the friends I am cool with knowing. Anyone else... nope. Too awkward.
But in this case, the person being a co worker... AND a new employee? No way would I bring that up to her.
Not everything that has the word tickle on it, is an open invitation to us to bring this up, or to tickle them. Unless it says TICKLE ME on their shirt. (I still woulden't recommend doing that to a co worker though. ) You'll probably be dissappointed with what she would have to say about it anyway. "I HATE IT"... could very well be her answer. So... no point.
If you like, just enjoy her in a fantasy, and let it be that.