What does Lauren do when he goes down on her?

Rot walked over and climbed into his bed next to his sister. He leaned in and kissed her and rubbed a hand across her breast. Lauren purred in his mouth and squirmed next to him.

She broke the kiss and whispered, "This is so naughty. My nipples are hard and I'm sooooo wet."

"So, do you want a titfuck or something else? I could eat you out?" he said.

Lauren gasped. "Guys don't do that!" she said. She sounded certain, not like she'd heard a rumor. Rot thought she was withholding something from him.

"You mean guys don't, but girls do? Who have you been practicing with? Wendy?" Rot asked, hoping his instincts were good.

Lauren looked at him shocked with her hand over her mouth. "How did you know? Now you won't want me because I'm a lesbian!" she whined.

"Oh, Lauren. Of course, I still want you! And if you want boys as well as girls, then you're not a lesbian. You are bi." he explained. "And even if you were a lesbian, I'd still love you."

"How do you know so much? Did you find some dirty book in the library?" she asked.

"Let's just say I did some research. Now, how about I show you that guys do it."

Rot leaned over and licked her right breast as his hand grasped her other one. When he sucked her nipple, he also pinched her other one. Lauren sucked air and arched her back. Rot could smell his sister's earthiness wafting up from her, so he knew he was having the desired effect on her. Once he had her panting hard, he climbed over her leg as he kept suckling her breast. His sister spread her legs wide, giving him plenty of room to get between her thighs. Then as he settled in, he released her nipple and moved lower, moving his hands up to fondle her breasts. He kissed his way down her belly, spending a little time, tickling her navel with his tongue. Lauren moaned and giggled, tousling his hair and stroking his back as he continued.

He kept moving lower, making sure to rub his chest down her mound. Then he saw her hair in the dim light of the room. Her pussy lips were flushed with blood and her slit exposed her glossy, wet cunt. He parted her hair above her slit and saw her clit, as big as the tip of his pinky, one of the biggest he'd ever seen. He lightly licked all around her lips and nibbled a bit on her flesh. His sister moaned louder, then covered her mouth to not let their parents hear them. Next, Rot licked from below his sister's cunt hole up to her clit and flicked on top of the clit for some time. She writhed beneath him, moaning.

When Rot latched onto her clit and sucked it like a nipple, Lauren groaned loudly. He stopped and shushed her.

"Oops, sorry," his sister whispered.

He went back to suckling her clit. Rot moved his hands to cover her breasts, playing with her nipples as he squeezed them.

When he pinched them, Lauren stifled a moan with her hand and whispered, "Oh, my God. You're as good as Wendy, maybe better." Her hips bounced up, pressing her mound into his face.

While he sucked her clit, his tongue danced on the tip of it. Her body wiggled more and more, and her squeaks got higher as he went, until in five minutes or so, she squealed into a hard orgasm and her juices poured out of the girl. He twisted her nipples, making her shriek for a second before clamping both hands over her mouth. Rot licked her juices as she came, and went back to sucking her. It took a couple of minutes for her to calm down from her orgasm.

"Where did you learn that? You haven't had that many girlfriends," Lauren said breathily.

He thought for a second, and then said, "I found a book in the library, hidden on a shelf. It was very good reading." He chuckled.