The Falling Devil would make for both a great inflator and inflatee.
1) she gives the victim//character/reader a specific, unnatural dish that causes them to swell uncontrollably, whether it be by blueberry, air, liquid etc.
2) she's the one getting inflated, whether it be by her own hand or another devil.
Just the thought of all those limbs puffing up and becoming useless, and that confident aura of hers breaking down due to embarrassment and horniness, is just PEAK.