The Pirouettes- Heros de Ville (Heroes Of The City)
 

Here is an animated music video for a French group called The Pirouettes. It involves a man and a woman chasing after one another in the city. He has the ability to fly and roughly half way through the video she grows to giant size.

The process for the initial growth unfortunately takes place off screen but while she is searching for him there is a bit where she does grow even bigger. It isn't too big of a spurt where she grows roughly a head taller (in proportion) before walking off to continue her search.

Check it out here

https://youtu.be/1XllOyw7_qg