The three started moaning more and more as the pleasure was just too much for them to hold in.
"When it's lubricated enough, you could just keep going, or you could slowly insert a finger inside.
But be careful. Your hymen is located here... This is sometimes how people determine if you had sex before.
It should be fine to put your finger inside as long as you don't insert something too big.
Remember, it's not the end of the world if it breaks. It slowly tears itself as you grow older, so it's sometimes out of your control."
As Katherine slowly inserted her finger inside her vagina, she bent it a little before moaning out again.
"Everyone is different, but there's a sweet spot that you want to touch——Hm!"
Seeing how loud she moaned out this time, all three of them slowly moved their finger inside.
Within a second, all three of them find their sweet spot as they out a high-pitched moan at the same time.
"In the future, you can also play with your boobs and nipple, but just focus on your sweet spot and the clitoris——Hm!"
All four of them didn't say anything else besides their moaning noise echoed the room as they kept teasing their sweet spot.
Soon, Sophia and Mary could feel something coming out.
"Mom, w-why does it feel weird——Hm!" Sophia asked as she could barely think straight.
"It's called climax——Hm!——That's when you finally reach your body's limit to the pleasure——Hm!——Just let it all out."
"Hm!"
Mary was the first to climax as a clear liquid flew straight out of her vagina, with her legs shaking a little.
Next, Sophia climaxed right after, shooting out a clear liquid as well as she clenched her legs together.
As the two girls recovered, Alex was at the breaking point as he could feel his cock was starting to feel painfully erect.
Unable to stop, his other hand slowly reached towards his cock as he began stroking it up and down.
Seeing Alex stroking his cock right before them, both girls looked a little shocked as they had never seen a guy masturbating.
Meanwhile, Katherine was about to reach her limit as well. Her eyes completely closed as she started to move her finger even faster.
"Hm!——I'm cumming!"
As Alex climaxed for the first time with his vagina, a clear liquid was shot right out along his cum coming out of his cock.
Feeling something hot on her legs, Katherine opened her eyes and realized the white stain that landed on her thighs.
For some reason, it turned her on even more as she finally couldn't hold it in and began climaxing.
Like her kids, she squirted out a clear liquid before calming back down. Then, in anger, she looked over at Alex.
"Alex, who told you to cum on your mother?"
Katherine questioned as her attempt to wipe the semen off her thighs was now stuck onto her finger.
"Sorry... I didn't know it could do that."
Seeing Alex genuinely looking down in shame, Katherine's heart softened after realizing he was still just a kid.
"Ahem, you three know how to masturbate now... Here's a helpful magic trick to get rid of all the mess."
As Katherine chanted a line, all the liquid and stains on her body and the bed evaporated.
"Just think with your mana and chant the line."
All three of them closed their eyes and focused as they tried to cast the same spell, which surprisingly worked.
"You three can go back to your room to sleep now... Remember, do this in private. Do not do it in front of each other."
The three nodded in agreement as they put on their underwear and pants before heading back to their room.
---
"Fuck. Why did I do this in front of them? What's wrong with me?" Katherine murmured as she laid back down on the bed.
With a snap of the finger, the light in the room turned off, with the door closing as she shot a light beam at it.
"No normal mother would ever teach their kids this kind of stuff with their own body...
But I'm a single mother, right? They're just going to forget about it when they grow older."
Katherine's mind started to look for excuses, as she felt ashamed for how weird she had been behaving.
More importantly, she couldn't believe she was turned on by her own son's cum landing on top of her.
"Come on, you idiot. They are your kids. You're just teaching them and nothing else.
It's nothing to be ashamed of. It's only going to be a one-time thing. Yeah, it's only a one-time thing."
As Katherine slowly justified her action, her mind was starting to feel twisted all over the place.
"It's never going to happen again, right? This shouldn't turn me on... But why am I getting wet thinking about this?"
After thinking for a bit, Katherine threw everything out of her head, shifting her attention back to going to sleep.
"I can't betray Paul..." Katherine thought to herself as she soon fell asleep on the bed.
---
Meanwhile, in the kid's bedroom.
"Alex... Was that what men's cum looked like?" Sophia curiously asked as the three of them lay down on the same bed.
"Yes..."
Alex's face blushed a little as he had no way of denying it after what they had done together.
"So that's the thing that mom said can make a woman pregnant..." Sophia murmured.
As the room fell into silence, Alex started to wish to sleep in a separate room from the two.
It was just becoming increasingly awkward for him, especially since Sophia was on his left while Mary was on his right.
"Mom and Dad must have had sex together to give birth to us, right?" Mary suddenly asked.
"Obviously. Or else we wouldn't be here." Sophia answered.
With the room returning to silence, the awkwardness disappeared as nobody spoke up again.
However, before Alex would fall asleep, he could feel somebody's arm on top of his chest.
"Sophia's sleep posture is so annoying..." Alex thought to himself as he turned to the side to push it away.
Once again, her arms wrapped around his chest, almost as if she was doing it on purpose.
But hearing her steady breathing pattern, Alex knew she was already in a deep sleep.
Trying to sleep, Alex tried his best to ignore it. Yet, he was hit with another challenge as Mary suddenly scooched back a little.
With Sophia's body pressing him from the back and Mary's body pressing him from the front, his mind was starting to go all over the place.
"Calm down. They are your sisters. Don't think of anything weird, and just go to sleep."
After hypnotizing himself for a bit, he eventually fell asleep on the bed.
---
The next day...
When Alex was awake, he could feel something warm in his hand and right in front of him.
As he opened his eyes, his hands were firmly holding onto Mary's chest, with her back against his chest.
Meanwhile, Sophia was hugging him from behind, wrapping her leg around his body like a body pillow.
After letting Mary go, he suddenly felt something wet above his pants, surrounded by warm flesh pressing against them.
For a second, he thought Mary had somehow peed the bed, but seeing the red mark on the blanket, he immediately realized what it was.
"Mary, wake up. I think you're having your first period."
"Hm? What did you say——Ouch! Why does it hurt so much?" Mary groaned in pain as if she had some sort of delayed response.
Alex immediately pushed Sophia's arms and legs aside to get up from the bed to the drawer.
After looking for a bit, he finally found the new pad and a pair of panties for Mary.
The noise made by the two of them also finally made Sophia wake up from her sleep as she slowly opened her eyes.
"Hm? Why are you two up so early——Oh my god, Mary!"
Sophia immediately got up from bed and ran out of the room to get Katherine while Alex carefully pushed the blanket aside.
"Mary, just relax. The pain will disappear on its own. Stop tensing up so much——"
"I can't! It just hurts so much——"
As Alex got ready to pull Mary's pants down, Sophia finally came back with Katherine.
"Mom, Mary's period came." Alex pointed out as he handed everything over to let her handle it.
Seeing the blood-red spot and Mary groaning in pain, Katherine quickly moved over to the bedside.
"Mary, don't worry. Mommy is here. Calm down a little, okay?"
Katherine's voice seemed to have some sort of magic as Mary finally stopped panicking.
Slowly, Katherine pulled Mary's pants and underwear all the way down, revealing the blood stain that had soaked the bed red below.
As a stream of water appeared in her hand, she slowly directed it to absorb all the blood on the outside before moving onto her thighs.
After all the stains were gone, Katherine attached the pad to the panties before helping Mary put it back on.