This is a variation of the "Mentos and Coke" "experiment," of which many videos of can be found on YouTube etc." where the mints react with the cola to produce a large amount of fizz, which if it's enough at one time, can produce a "geyser" sort of eruption from the bottle. This differs partly in the brands of cola and mints, but mostly in being done by a woman who is dressed for the occasion: swimsuit, swim cap and goggles--in other words, dressed to get wet! Nataly maybe "cheats" a bit by shaking the bottle, but still, there's some spectacular explosions of Pepsi all over her and the walls of the shower, especially later as she gets into her stride, sometimes holding her hand over the top of the bottle as she shakes it, leading to an explosion when she releases the pressure. She also pours the remaining Pepsi over her head, so the swimsuit gets soaked in it, and the goggles do their job to keep it out of her eyes as it pours down her face (all of which nicely fulfils my "swimwear getting wet with liquids other than water" fetish).