A Lesson in Biology
Copyright© 2026 by Lubrican
Chapter 2
Coming of Age Sex Story: Chapter 2 - She wanted to be a cheerleader but her grades were too low. Summer school might solve that problem. But she needed a tutor to make sure. Her mom got a name from the school and he was hired. When they got to the biology tutoring, she wanted to understand the reproductive system. He was happy to teach her about it.
Caution: This Coming of Age Sex Story contains strong sexual content, including mt/ft mt/Fa Mult Teenagers Consensual Heterosexual Fiction Incest Mother Son Brother Sister Harem Interracial Black Male White Female First Lactation Masturbation Oral Sex Petting Pregnancy Voyeurism
There was only half an hour before Robin’s mom was supposed to get home. They used that half hour to explore kissing. Marcus, of course, had kissed his mother and sisters as he fucked them and Robin had kissed boys she dated quite a lot. But these kisses were somehow different. They were somehow more intimate. If they’d had an hour to kiss they would have ended up naked again.
But they didn’t, and Marcus was gone by the time Molly got home. She had been at a fundraiser for the Humane Society Shelter and had learned something that pissed her off royally. She had learned that her husband, Brad, was cheating on her with his intern at work. The intern was in college and two of her friends were at the fundraiser. One was the roommate of a girl named Crystal, who had been bragging about how she had scored a sugar daddy where she was interning. Then Brad’s name came up.
“He’s married, but he says he’s going to get a divorce,” said the girl.
So, when Molly got home, she was not a happy camper. She went looking for a fight with her daughter, but found the girl studiously studying, which calmed the woman down.
“How was your tutoring session?” she asked.
“Fine,” said Robin, as if it didn’t matter. “He makes things easy to understand.”
“Good,” said Molly. “I don’t care about the cheerleading. I just want you to be able to get into a good college and good grades and good SAT scores are the way to do that.”
“I know, Mom,” drawled Robin. “My test scores are getting better and better.”
“What’s he like?” asked Molly, who was just trying to make conversation that was normal.
“You mean Marcus?”
“Yes. He comes from different people than we do. Has there been any friction?”
Robin thought about the friction of Marcus’s finger in her pussy but pushed that thought aside before she blushed.
“His mom is a single mom and he has two sisters,” said Robin. “He has to work to supplement their income.”
“So he has other students?”
“Yes, but I don’t know who. Why are you asking this?”
“I don’t know. I guess I’m just curious. I was raised in the south and was taught not to talk to black people. Now I understand how foolish that was. I’ve never spent five minutes with any black people so I don’t know what they’re like.”
“They’re like anybody else, Mom,” said Robin. “Cut Marcus and he’ll bleed red.”
“I want to talk to him,” said Molly. She could not have articulated why she had decided that.
“Why?”
“I don’t know!” snapped Robin’s mother. “He spends hours alone with my daughter. He’s a man, or at least he looks like one. I worry about you.”
“Mom, Marcus doesn’t have a girlfriend. He doesn’t go on dates. A lot of kids think he’s gay and in the closet. He doesn’t show any interest in girls at school the way all the other boys do.”
“So you don’t want me to talk to him.” Molly’s voice was hard.
“I didn’t say that,” said Robin. “You can talk to him all you want to. You’re paying him by the hour and if you want to pay him to talk to you that’s your business. He’s a teacher’s aide at summer school, so I’ll see him tomorrow. I’ll ask him if he can give me four hours Thursday night instead of three.”
Molly almost said not to worry about it, and that she didn’t need to talk to the boy. But Brad’s indiscretion had her angry and she wanted to do something different ... crazy. And spending an hour talking to a person from a completely different social class might be what she needed.
The next day Robin got Marcus off in a corner and told him what her mother wanted to do.
“Does she suspect something?” he asked.
“No. She was acting weird, like something was bothering her, but it didn’t have anything to do with me.”
“Okay,” he said. “I’ll talk to her as much as she wants. She’s paying me by the hour.”
“That’s what I told her,” said Robin. “I’m upset that we won’t be able to do any foreplay, though.”
“Me, too. Maybe I can come over some night when I’m not tutoring.”
“Dad is gone for another week before he gets back and Mom volunteers at a dozen places. I’ll find a night you can come over.”
“Great,” he said with a smile. “I wish I could kiss you right now.”
“I wish you could suck my nipples right now,” she replied, with her eyes peering through her eyelashes.
“I’d get a boner,” he said, softly.
“Why do you think I want you to suck my nipples?” she asked.
“I thought because it feels good to you?”
“Well of course I love how it feels. But I love it more when you get hard because of me.”
“Now I’m going to be hard for the rest of the day,” he said.
“Well don’t let Miss Carson see it that way.”
“Why?”
“She just broke up with her boyfriend and she might be on the prowl. I don’t want her prowling my penis.”
“So it’s yours, now?” He smiled.
“Well, it’s the only one I can want, and I want it most of the time, but I guess you actually own it.”
“Thanks so much,” he said.
“I have to go. Can you come early?”
“I’ll cum early,” he replied, using the word completely differently. He planned to masturbate before he went. Molly Fitts was as good looking as her daughter and it was easy to imagine her naked. He knew that, being married, she had fucked plenty of times and wouldn’t be shy, as long as she was interested. Of course he didn’t expect her to be interested, but it was a fun fantasy. He even had one fantasy in which Molly and Robin were side by side, naked, as he hopped back and forth between them, giving one an orgasm and then moving to give the other an orgasm.
“And don’t wear those shorts that let your penis come out,” said Robin. “I don’t want my mother to see that. She’d freak.”
Molly Fitts had her own social circle, and it included Marsha Wells, whose husband was a lawyer. Not only was he a lawyer, he knew some divorce lawyers. Molly got a referral and an appointment through Marsha’s husband. She wasn’t going to wait for Brad to start divorce proceedings. The appointment was a week later, though, so Molly had to act like everything was normal for that week.
She and Brad had separate bedrooms. That was because Brad said she snored and moved around in the bed too much and his sleep was suffering because of it. Now she suspected that it was because Brad was using all his fucking energy on some girl, which was why he had showed no interest in her, sexually, in months. She had just thought it was because he always came home exhausted. Now she suspected the exhaustion was an act.
She knew how divorce usually played out when wealthy people were involved, so she knew she would need some kind of evidence to claim he had broken their wedding vows, if she was going to come out of a divorce with any money in the bank. Another of her friends knew a private investigator, in relation to her own divorce. She got his number “for a cousin who needed such services” and called him. “Him” turned out to be a “her” but the investigator was was eager to help, primarily because she recognized the name. They were rich and she doubled her usual retainer and fee.
Thursday night Molly couldn’t decide what to wear to talk to this young black man. So she asked her daughter about that.
“Mom, it’s not a party,” sighed Robin. “Just wear normal clothes.”
“I was thinking about swimming before he came. Would it be inappropriate to talk to him in my swim suit?”
“If you don’t mind him ogling you,” said Robin with a smile.
“Why would he do that?”
“Mom, you’re gorgeous. That swimsuit might be a one piece but it fits you like a second skin. You didn’t like the bulges the modesty panels made so you took them out, remember?”
“Yes.”
“Well, if I can be blunt, whenever you wear that and it gets wet, your nipples show and so does your camel toe.”
“No it doesn’t!” gasped Molly.
“Yes, it does.”
“Brad never said anything about that,” said Molly.
“That’s because he never looks at you when you get out of the water. He’s always got his nose in the Wall Street Journal or something.”
Molly’s emotions boiled over. That simple comment: “He never looks at you,” caused her tears to start spilling down over her cheeks.
Robin was alert instantly. Her intuition sensed something was wrong ... badly wrong.
“What’s wrong, Mommy?” she asked going to hug her mother.
“I can’t tell you,” sobbed Molly.
“Of course you can. We talk about everything, remember?”
“I can’t talk about this,” groaned Molly.
It took fifteen minutes but Robin finally got her mother to talk. She got upset, too, and angry with her father.
“And you’re going to have the private investigator watch him?”
Molly nodded. “I don’t know what to ask her to look for, though.”
“She does that for a living. She’ll know what to do. Okay. Good. So we have a plan.”
“It isn’t ‘we’, Darling,” said Molly. “This isn’t your problem. Whatever happens Brad is your father and he’ll always be your father.”
“Marcus’s mom is single because her husband took off with some woman. It’s made it hard for them to get by. If my father causes us to have to live that way he can go suck an egg as far as I’m concerned.”
“Well, this is a community property state, so I’ll get half of everything. We won’t have any problem with living expenses.”
“Okay. Go swimming. Work off some stress. And when Marcus gets here I’ll bring him out to the pool. If Daddy won’t look at you, I promise you Marcus will. Just watch his eyes. He’ll convince you that you’re still beautiful and desirable and Daddy can go suck eggs.”
Molly did not think that through. She was too upset. She just let Robin take charge.
She just went with it, as well.
She went and put on her suit.
She did not think to re-install the modesty panels.
When Marcus got there it was six. It was high summer and the sun had not set, yet. She had told him to come early. Robin was wearing a robe and brought him up to date.
“I know how badly that sucks,” he said, giving Robin a hug.
“I’m going to take you out there. When she gets out, I want you to look her up and down. Her nipples will be showing and probably her camel toe, too. I want you to look at them.”
“Why?” he asked.
“I want her to see in a man’s eyes that she’s beautiful and desirable,” said Robin.
“You want me to get a boner for your mother?”
“It doesn’t have to be a boner. Just show her that you think she’s pretty.”
“This could be a bad idea,” he said. “Didn’t you say she was raised in the south? What if she gets pissed off that a black kid is staring at her and kicks me out. You and I would never be able to see each other again.”
“You just trust me,” she said. “I have a plan.”
She undid the tie on the robe and pulled it open. She was wearing a bikini, and it was a small one.
“I’m going to tell her I’m going to swim while you two talk.”
“Okay.”
“I’ll notice her nipples and camel toe first and say something about them. That will give you a reason to look.”
“I think you’re crazy, but what the hell?” sighed Marcus.
“Good.”
Robin pulled his head down for a scorching kiss, retied the robe, and then grabbed his hand and pulled him toward the patio doors that led out to the back yard and pool.
If it seems to the reader that things happened rather quickly between this young couple and without any planning, that is true. Actually, nothing at all happened for the first month, as they got to know each other, which established a kind of trust and ease in each other’s company that avoids sexuality, at least on Robin’s part. When Robin suddenly found herself with options she would normally not have had, the newness of the situation caused Robin to react much differently than if she had known what to expect. But the experience had been entirely positive. Robin had felt ecstasy of a kind she had never experienced, before, and she reacted like someone does when they try smoking crack. It’s addictive ... instantly ... and Robin accepted this new addiction without even thinking about it. She might have been innocent, in terms of sexual experience, but she had been bombarded with sexual messages all her life, just like every other woman in western culture. Advertisements tell a woman how to dress, walk, smell, talk, and every other part of making her “be” sexy. Robin was just discovering what “sexy” actually meant, but she had soaked up the advertising.
She stood, letting go of Marcus’s hand and waited for her mother to swim to that end of the pool. Molly swam a hundred laps a day and it was part of a regimen that kept her in fabulous shape. When she saw the youths, she stood up.
“Hi,” she said, looking up at Marcus. He looked ten feet tall from her perspective, and very, very black.
“Hi,” Marcus returned. “Robin says you want to talk to me about something?”
“Just talk,” said Molly.
She put her hands on the edge of the pool and jumped out of the water like a seal, with no effort. She went to a chair nearby and picked up a towel, which she used to dry her jaw-length auburn hair. Robin continued with her plan.
“Mom! Didn’t I talk to you about that swim suit?”
“What?” Molly’s mind had been racing, even while she swam laps. Her mind was tired and she didn’t have the capacity to reason that she normally did. She did remember talking about the suit, but that was all.
“Your girly parts are all showing, for Pete’s sake,” said Robin, lifting her hand to “cover” Marcus’s eyes. “Marcus can see everything you’ve got!”
Molly looked down and felt herself blush. She looked up to see Marcus moving Robin’s hand away from his face.
“I’ve met your mother,” he said. “Remember?” He didn’t give Robin time to say anything. “I know she’s a woman and I know she’s beautiful. I see no reason for her to have to alter her life just because I’m here.”
“But you’ll look at her,” complained Robin.
“So? Is that any of your business, really? I’m your tutor, and the only things you and I should discuss are tutor-reflated things. Your mother is a big girl. Didn’t you say you were going to swim while I talked to your mom? So, there’s the pool. Go swimming.”
Robin had a hard time preventing herself from smiling. He sounded so serious, so masterful. He sounded powerful, somehow.
“You don’t have to have a cow,” she groused. She undid her robe and slipped out of it. She tossed it on a chair and whirled.
“Am I beautiful, too?” she asked.