This design is an example of form, but more specifically, naturalistic form. Naturalistic is when the design is derived from anything in nature, or a human figure. This particular form is a human figure, which makes it a naturalistic form.
Pluto and Proserpina. The Rape of Proserpina is a large Baroque marble sculptural group by Italian artist Gian Lorenzo Bernini, executed between 1621 and Bernini was only 23 years old at its completion.