It's rude to upskirt women.
Pierre is at the crowded mall which is two stories with lots of escalators.
Pierre wants to entertain himself.
Pierre checks out his favorite shop in the mall and does a little shopping for himself.
Pierre walks around on the first floor of the mall looking upwards to the second floor to try to find views of women who are wearing skirts.
Pierre enjoys the experience and feels good about his purchases.
Pierre is reported by somebody to mall security for being a pervert, and he is publicly reprimanded which is deeply embarrassing for him.