Roy's pose reminds me of the rampant attitude in heraldry, picrel (a rampant lion).
>2.
>Heraldry
>(of an animal) represented standing on one hind foot with its forefeet in the air (typically in profile, facing the dexter side, with right hind foot and tail raised).
>"two gold lions rampant"
There's another meaning of rampant, however.
>adjective
>1.(especially of something unwelcome) flourishing or spreading unchecked.
"political violence was rampant"