The scene could portray the man in a somewhat clumsy manner while putting on the pants, perhaps with one leg in and the other still out, and a bit of a disheveled look around him.
Maybe he's getting ready for the day or has to go out.
Maybe the pants are too small or the cartoon man is not coordinated. It could just be a funny situation for entertainment.
The scene might show a man sitting on a bench in a park, enjoying the view. Maybe he's thinking or waiting for someone.
The man might be enjoying the view, perhaps lost in thought or simply taking a break.
The cartoon might show the girl carefully stepping into the pants and pulling them up slowly.
It might be a cartoon in a fantasy setting where the girl's pants have magical properties and putting them on leads to an exciting adventure. Or it could be a slice-of-life cartoon showing a normal girl's everyday struggle with getting dressed quickly.
The scene might show a cartoon man sitting peacefully, looking around, or it could be that he's sitting with a worried expression, depending on the context.
The scene could depend on the context. If it's a comedy cartoon, he might be sitting in a funny pose. In a serious one, he could be sitting solemnly, deep in contemplation. There are many possibilities.
The scene of a cartoon old man sitting might show him in a garden chair, reading a book or just taking a break from a busy day.
It could be a man having a meal peacefully at the table, maybe with some food and a drink in front of him.