The Playboy cover girl appears nude in the ad encouraging people to turn into 'angels' by adopting pets instead of buying them.
In one ad Krupa is seen wearing wings while a strategically placed crucifix covers her. In another one, the topless model again wearing wings holds a dog while a rosary dangles from her arm.
"The fact is that cats and dogs are a lot safer in pet stores than they are in the hands of PETA employees," Catholic League President Bill Donohue said in a statement.
"Moreover, pet stores don't rip off Christian iconography and engage in cheap irreligious claims. PETA is a fraud. Those who support this organization sorely need a reality check. They also need a course in Ethics 101," the statement added.
Responding to this, the former 'Dancing with the Stars' contestant, who is a Catholic herself, said, "I'm doing what the Catholic Church should be doing, working to stop senseless suffering of animals, the most defenseless of God's creation."