The leather felt unusually warm as Alice slid it around her neck. The silver buckle tingled beneath her touch as she fumbled the strap through it. It was a perfect fit, of course, that had been one of the many demands she had made. She turned the collar so that the pink gem hanging from it settled just above her collarbone. As soon as her hands pulled away from the leather she felt it activate. A wave of warmth spread through her and held. She would not have to worry about staying warm while wearing her new collar, one of its many features. Another feature made itself known, a feeling in her gut that, yes, the collar was active and she did not have to worry about anyone seeing through it.
Grinning like a chesire cat, she reached up and removed the scrunchie holding her hair in a bun and let it cascade down her back in a luxuriant wave of red locks. She stretched and gave herself a thorough once-over in the mirror to make certain that everything was present and correct. Nothing had changed as far as she could see. Still 5'4 and thin with perfectly pale skin. She checked her eyes. Still green and human. Good. She reached up and hefted her breasts, or at least she would if really had any to speak of. There they were, still stuck on the border between B and A, impossible to find a bra that fit them right. She grinned again. With this collar she wouldn't have to wear a bra ever again if she didn't want to. Assured that the old man hadn't slipped any weird transformations into her new toy, Alice turned to her bedroom door. There was one last test. Not allowing herself any time to second-guess the sanity of what she was about to do, Alice opened her bedroom door and walked down the hall to her sister's room.
15 year old Brittany Miller was, in many ways, the opposite of her older sister. Tall, blonde, fit, and well on her way to being the star of both the gymnastics team and cheer squad. She stood in stark contrast to her shorter, thinner, nerdier sister. They got along okay though. Alice may be the school's nerd princess, but everyone at least liked her. She suspected that Britt may have had a word with some of her popular friends, but she honestly didn't care what they thought of her. Right now all she cared about was whether the main function of her new collar worked or not. Britt's door was open so Alice strode in without bothering to knock. Britt looked up from her phone but didn't react in the slightest to the sight of her naked older sister dripping pussy juice onto her bedroom carpet. She gave a grunt of acknowledgement and went back to whatever chat she was having with her friends.
Alice was ecstatic. Here she was, naked and very obviously aroused, and Britt acted exactly like she usually did. She almost came right then and there. Quivering with excitement, Alice practically bounced her way across the room and hopped up onto her sister's bed. She scooted herself right up next to her sister and spread her legs wide. Her inner thighs were slick and shiny now, and her thick red bush was so wet that from the waist down Alice looked as if she had just gotten out of the pool. Britt just gave her a somewhat bored look and sighed.
"Oh," she said in mock surprise, "You want me to pet you huh?"
Alice responded by pushing her hips out more. She was so close to orgasm that she could have screamed. Britt sighed again, then put her phone down and reached towards her sister's sopping cunt. She ran her fingers through the thick tangle of pubic hair until she found Alice's clit and started rubbing it with her thumb. Alice fell back on the bed and gasped in pleasure. She was so close now, just a little more. Britt seemed to know exactly what to do. With her other hand she slipped two fingers into Alice's hole and dragged the tips along her g-spot. Alice came instantly with a bestial growl of pure pleasure. The world went white around her as she struggled to regain her breath. When she finally pulled herself back down to earth she sat up shakily and tried to thank her sister.
"Tha-" she managed to gasp out before the sight of Britt's face caught her up.
If looks could kill then Britt's might have been in the running, but would have been disqualified for the amount of fluid covering it. Alice had never been much of a squirter, until now obviously. She gave her sister a sheepish look. Britt just rolled her eyes and climbed off the bed.
"If I find out you did that on purpose," she admonished, "You can start begging other people for pets."
Alice just grinned. This collar was the best thing ever. She lay back and watched her sister strip out of her wet clothes, something she would not have been allowed to do before. The collar made it possible. In her sister's eyes Alice was now nothing more than an animal, a human one, but an animal none the less. She could do almost anything and everyone would just write it off as: "Something Alice does. She can't help it really, she's just an animal." She had been meticulous when writing the rules of the collar. So long as she didn't deliberately cause someone physical harm she could do anything. She would have to thank that old man in the shop for making it to spec. Much better than trying to find an off-the-shelf solution and worrying about it going wrong.
She watched as her sister removed the last of her clothing. Alice had long ago given up comparing the two of them. Britt was almost six feet tall now and had the kind of lean muscles you only get from daily light workouts. Her long blonde hair was a perfect curtain of gold and matched her well-trimmed pubes. The only thing Alice truly wished she could have was her breasts: perfect C-cups and still growing. Britt wrapped herself in a bathrobe.
"Alright," she said, pointing at the door, "Out you foul beast. I need to go take a shower now and I'm not about to leave you here to drool all over my stuff."
Alice hopped off the bed and scurried for the door.
"Augh! You got my bed all wet too! You're lucky you're so cute or I'd have mom kick you out!"
Alice just laughed and skipped down the stairs. She made her way to the back door and burst out into the warm summer sunshine. She spent a moment basking in the sun's rays, no longer worrying about sunscreen. The collar would protect her from the elements, as designed. She ran several laps around the lawn, just for the sheer joy of it. At one point she realized that she had to pee and almost ran back inside to use the bathroom, but changed her mind. She considered squatting in the lawn for a bit, but decided that it would be far more fun to just let it flow while running wild. Soon her legs and feet were covered in a mixture of piss and her own juices. Alice didn't care how much of a mess she made of herself, she was having the time of her life.