Time for one muttered prayer before you launch yourself from the cleaning station, passing through the air and dropping toward the expanse of denim.
Thudding into the solid surface, you slide painfully down its rough exterior as you scrabble wildly, your fingers losing skin as they dig at strands thicker than your arms. Your fall halts, and you have a moment to catch your breath and contemplate your survival. Just a moment.
Then the woman moves, a simple step to the side that creases a contortion all across the wall of fabric to which you cling, deforming it to the whim of her godly thigh muscle, and shaking you wildly. It's all you can do to maintain a grip; any dream of descending to the floor dies here!
Terrified beyond description, you cling tight to the jeans, afraid that any movement may coincide with the giantess moving, and casting you, screaming, to the ground so far below. You're stuck here for the foreseeable future, waiting for a chance of the woman ceasing movement for a guaranteed period of time before you try to get off.
So you wait, listening to the cooing of the mother over her daughter, and narrowly avoiding becoming crushed between a fold as she stoops to place the toddler back in the stroller. The rise upward is more exhilarating than any roller-coaster, but then she begins to walk.
The leg swings back and forth, and you doubt any mountaineer would stay attached better than you are right now: this is akin to climbing the slope of an exploding volcano!
Motion ceases, and you blink a few times before looking over your shoulder. You can make out the hazy form of the library's front desk, close enough to leap across to, and with a rough enough surface that gripping should be a cinch. You don't risk it yet though, listening for any indicator of sudden movement on the woman's part:
"Just the one today?" the amiable voice of the librarian booms down.
"Yeah, I hardly get any time to read with this little bundle!"
"Heh, yeah, tell me about it! See you next week, then!"
She's checking out a book - perfect! You can jump to the front desk with time to spare!
Although... This woman will be returning here in a week. You could stay with her, allow her to take you home with her. While the library is desolate, devoid of food, the house of a family will be plentiful. You could gather lots of supplies there, and if you stowed them aboard the stroller - invisible to a regular human eye - you could have the woman bring you and them back to the library in seven days' time! Then, suitably outfitted with supplies, you'll have reserves to fall back on while you build your new life here in the library!
Thirdly, here's your chance to return to the streets, the original plan you set out to survive. Once this woman's out the door of the building, you get the Hell off her and try survival here on Hard Mode.