Kendra heard the front door open and shut. Then her sister, Lily, walked into the living room and stopped in her tracks and stared in shock.
"Kendra?!" Lily asked. The half-snake creature before her looked like her sister from the waist up, but it was still hard to believe.
"Of coursssse" replied Kendra. She unwrapped her tail from around her and rose up to the height she would have had with her legs.
"I've been wondering what you looked like as a lamia. Mom would never let me see you transformed."
Lily walked closer. "You've been masturbating, haven't you?"
"Of courssse. I can't help myssself like thisss."
"I remember that day you lost control of yourself, pinned me to the floor in this very room, and started ripping of my clothes."
Lily was close to her sister now. "I was scared at first. But then it started getting me turned on. I wish mom hadn't stopped you. I ran off to my room after that. Mom though I had been crying. I'd actually been masturbating, imagining you having your way with me as a lamia."
Lily put her arms around Kendra's shoulders. "Mom shouldn't be home for at least another hour, maybe two. And as of last month I'm 18 so I can legally consent to whatever perverted stuff I want to. Even lesbian incest with a lamia."
Lily pulled Kendra into a kiss, which she eager reciprocated, wrapping her arms around Lily. The sisters kissed in a way they never had before. Suddenly Kendra threw Lily on the floor and pinned her down. Lily smiled at the callback to the earlier encounter cut short. Kendra used her claws to rip Lily's blouse open and her skirt off. Then she began to tease Lily's nipples with her snake tongue. Lily's breasts were large A's and she had always been jealous of Kendra's big B's. Now she was especially jealous of Kendra's huge D's, and began to fondle them.
Kendra teased her way down Lily's stomach to her vagina, which was already wet with anticipation. Kendra's snake tongue plunged in, but she was careful to keep her fangs retracted. Lily lay back as her sister pleasured her with her amazing tongue. Plunging deeper and deeper.
"Yes, Kendra, yes, keep going..." Lily cried out.
Kendra drove her sister to orgasm after orgasm. When it seemed like no more climaxes were forthcoming, Kendra lay back into her own coils while licking her sister's juices off her lips. The oral sex had gotten Kendra aroused again and she would pleasure herself again as soon as she caught her breath.
Before she could, Lily summoned the strength to crawl over to her sister and kiss her.
"Thank you so much for that" Lily panted. "I don't think I can truly return the favor, but I'm going to try."
"Yesss," hissed Kendra, "pleasure me and drink my juices. Then you will become like me and know true ssssexual ecstasssy, beyond what I could even ssshow you today."
Lily tried do do what she could with her tongue, but Kendra was too big as a lamia, especially after her earlier masturbation. Lily switched to her fingers then her entire fist, driving Kendra to a series of orgasms. Then Lily hungrily lapped up Kendra's juices, eager to become a lamia too.