Cast with a kiss.

Alison turned to Walison the moment the computer screen went black. She pulled at the knots securing her twin's ankles and wrists, freeing her with a little difficulty. Walison rolled herself over, sitting on the edge of the bed with Alison kneeling beside her.

"Are you ready for the spell?" Alison asked eagerly, her soft female voice trembling with excitement.

"Are you certain you want to do this?" Walison replied, her male voice gruff from age and dubious. "If I sound as you do, then it would be impossible to tell us apart unless I gave myself away in conversation or action."

"That is the whole point, silly," Alison affirmed enthusiastically. "We will prank Peter. I bet he cannot tell us apart."

"Unless you have a spare college uniform for me to wear, it is obvious," Walison pointed out.

"No problem," Alison dismissed the objection. "I might not have clothes to dress you in, but if I am naked too works just as well."

"Ready? One, two, three," Alison counted down. "VOX FURANTOR REPONERE!"

Despite her continuing doubts, Walison joined her voice to the incantation. Her tongue, lips and mouth seemed to tingle slightly as the last word was uttered. Before Walison could react and ask if Alison felt the same sensation, slim female fingers grasped each side of her head. Alison leaned in and her full lips locked upon Walison's mouth. There was a heartbeat of hesitation, which dissolved as Alison's lips parted her own and an inquisitive tongue thrust into her mouth in fevered exploration. Walison found herself returning the passion of the French kiss without further hesitation, her lips and tongue much softer and sensitive now, and the kiss more enjoyable than she thought possible.

Their tongues fenced and darted, sliding and duelling with one another in sensual competition. Alison's tongue was fresh tasting and as soft and agile as her own. The sinuous flesh thrust, parried and riposted like rapiers for much longer than was necessary for the spell. When they finally unlocked lips and drew back far enough to look at each other, both girls were out of breath and panting with red flushed cheeks.

"Did it work?" Walison asked, hearing her voice as young and sweetly female as Alison's. "Oh! My voice, your voice. It worked, I sound just like you.