They decide to play a bit with Lisanna's magic.

"So... How about taking on a cat girl form, and I take you from behind?" Natsu suggested.

Lisanna grinned, feeling the compulsion to obey, and not resisting it. "Animal Soul: Cat," she intoned, taking on her cat girl form with the Takeover Magic. She deliberately left out the bikini that came with the form. Her tail began to flick back and forth as she gazed at Natsu. "So... you want me to call you Master now?" she purred, blushing from both arousal and a bit of embarrassment.

Natsu considered it for a moment, before he said, "While we're doing sexy stuff, yes. Get on all fours." As Lisanna sunk to her hands and knees, Natsu turned to Lucy. "Lucy, why don't you lay in front of Lisanna, then reform your legs so you can spread them?"

"As you command~!" Lucy grinned as she floated down to the floor and her tail remade itself into her legs once again, which she eagerly spread for Lisanna to start licking her exposed sex. Natsu knelt behind Lisanna, and began to finger her folds, making her moan in delight. She tentetively moved her face down and extended her tongue to lick Lucy's snatch. Lucy jolted in pleasant surprise. "Oh... your tongue's a bit rougher than normal..." she moaned.

Lisanna grinned as she looked up at Lucy. "I let the Takover Magic influence it a bit, it's now a bit more catlike. I thought it might add to the stimulation..." She then gasped as Natsu slid his length into her from behind. "Oh... that feels so good, Master..." Lisanna mewled. She resumed licking Lucy's snatch, making the genie squirm under her enhanced tongue.

"This is really hot," Natsu moaned as he placed his hands on Lisanna's ass, and began to slowly fuck her. Her tail began to flick back and forth lazily in front of his face. "...hey, Lucy, I wish that Lisanna's tail was erogenously sensitive to my touch specifically," he grunted as he kept going.

Lucy nodded, biting her lip and snapping her fingers, before cupping her own breasts in her hands while bucking her hips into Lisanna's face. He proceeded to grab Lisanna's tail, and sped up, stroking it. Lisanna jolted and gasped. "Oh... oh god, that is so good," she panted out, replacing her tongue with her fingers in Lucy's entrance.

As the fucking continued, their pleasures rising, Lisanna returned to licking Lucy's pussy, while mewing at every tug on her tail. Natsu was pounding into her before long. Lisanna could barely focus on giving Lucy pleasure, but Natsu gave her an order to get her off, which helped via the compulsion, and she began to finger Lucy's pussy, and lick her clitoris. This caused Lucy to get off, and she cried out, her hips thrashing as she came.

Natsu and Lisanna weren't far behind, and Lisanna gave a loud mewl as her vaginal walls clamped down on Natsu's cock, and he grunted, and filled her with his essence. "...my balls are going to be constantly empty at this rate..." he panted as he pulled out of Lisanna, who was wheezing as well.

Lucy, having recovered from her orgasm, giggled, and looked at Natsu. "A simple wish can fix that!" she chimed.

"Tempting," he chuckled.