Venelana climbed onto the bed and took his dick in her hand…
"First, like this, kiss, kiss──"
Venelana showered the head of Kazuki's glans with a rain of kisses.
"The glans is the most sensitive part of the penis. So, when you stimulate it like this── see, the pre-cum is starting to well up."
Stimulated by her soft lips, Kazuki's cock overflowed with pre-cum from the glans, producing lewd, wet, squelching sounds.
"Fufufu. It's getting nicely wet now~!! Go on, you try it too. But don't just put it in your mouth right away. Here, like this───"
"Umm, like this...?"
"Ugh, ugh, ahhh...!"
Guided by Venelana, Rias diligently ran her tongue from the shaft up to the glans. Kazuki's cock was soon coated with a mixture of his pre-cum and Rias's saliva.
"Playing with this part is also very effective.── Ahnmu, kiss slurp slurp..."
Saying this, Venelana took Kazuki's testicles into her mouth, rolling them around with her tongue.
"Kuh, ugh, ahhh!"
Overwhelmed by the unfamiliar sensation, Kazuki let out a tormented moan.
Perhaps sparked by a competitive urge against her Okasan for eliciting such sounds from Kazuki, Rias took the glans into her mouth.
"Nmo, nmu, squissh... chuba, slurrrp!!!"
"Lick, hmmm, ero... nnnn... ufu, slurrp~!!! Rias, since you have it in your mouth, make sure to look at Kazuki-san's face properly."
Doing as she was told, Rias looked up at Kazuki with upturned eyes.
"It's not just about having his dick in your mouth. You need to explore what licking where feels good for him, to learn his reactions as you lick."
'Now that she mentions it, until now I've just been licking frantically without thinking... In that case, what if I try this...?' Rias thought.
While keeping the cock in her mouth, Rias slowly traced circles around the glans with her tongue, causing the member to twitch violently.
'Did that feel good...?'
Encouraged by Kazuki's reaction, Rias happily grew more proactive, experimenting with different movements of her tongue.
"Ufhn... chu, lick, chupu... nnn, Slurp slurp, mufhn, chuu, chu... kiss slrrrp, aahn... Hmmm!"
Taking care not to let her saliva spill, she showered the glans with pecking kisses, ran her tongue along the frenulum and the coronal ridge, sipped the pre-cum overflowing from the slit, and after taking the cock back into her mouth, she sucked on it strongly.
"Nnn, n-oohh... R-Rias!"
Kazuki trembled with pleasure from this new, different kind of blowjob from Rias. Seeing Kazuki like this, Rias formed a satisfied smile on her face.
"Fufufu, well done, Rias. Next, try making more sound. The lewd, slurping noises you make will heighten Kazuki-san's arousal even more."
Pleased by the praise, Rias did as Venelana said, licking and sucking the cock while producing vulgar, wet sounds.
"Slurrrp! Ahhh! Hmmm! kiss... nfuu, lero! slrrrp!"
"Kuh-ohhh, Rias, I'm about to──!"
Driven to the edge by the exquisite tongue work of both Rias and Venelana, Kazuki reached his limit.
"That's it, do it inside her mouth, Kazuki-san! Fill Rias's mouth with your hot seed! Give her a full load!"
Shouting this, Venelana thrust her finger into Kazuki's anus.
"! Uwaaaahhh!?"
With her finger inserted and bent into a U shape, stimulating his prostate, Kazuki couldn't hold back any longer and exploded…
Splurrrt… Splurt! Spurrrt!!
"Mfuuuuuuuuuuuh!?"
Rias gulped desperately, her throat sounding as the massive wave of semen flooded in.
However, the sheer, ferocious volume was too much to swallow completely, and frothy, milky white fluid spilled from the corners of her mouth.
"Bffuuhh!!... Bffuh... nnn, Gkyu, gullp... nnnn... Incredible... so much..."
Even after Rias removed the cock from her mouth, the semen continued to shower down.
Her face, tear-streaked and choking, was stained white, and the viscous white fluid overflowed onto the valley between her breasts, forming a small pool.
"My, my, what tremendous force... Rias, you must strive to drink all of the semen he ejaculates. Semen consumption is one of the acts that most pleases a Master, satisfying his desires for conquest and domination. This single act alone can put a Master in the mood."
As Venelana rubbed her back, Rias nodded.
"Huff, huff... Yes, I will do my best."
"...Even so, Kazuki's cock is truly amazing. It shows no sign of weakening at all. With this, it should be possible very soon."
Saying this, Venelana moved behind Rias and made her spread her legs wide open.
"Kyaah! O-Okasan!?"
"Come now, Kazuki-san, come here."
Ignoring the surprised Rias, Venelana urged Kazuki to insert himself. Although bewildered by this unusual situation, Kazuki pushed his cock into Rias's wet, dripping pussy.
"Aahhh!... Kazukii!!!"
Familiar with the sensation, Rias let out a cry of joy. Kazuki began moving his hips fiercely as usual. But Venelana called a halt to Kazuki's actions.
"Wait, Kazuki. Fucking her fiercely is important, but that alone is not enough. Try incorporating more variation in pace."
"Variation in pace...?"
"Yes. Just as you might use feints in combat, correct? Sex is the same. Watch your partner carefully, probe to find her weaknesses, and move accordingly."
'...I see. That makes perfect sense.'
Agreeing inwardly with Venelana's instruction, Kazuki slowed the movement of his hips. Instead of thrusting in deeply, he pushed in slowly and pulled out slowly.
'Ah, this might be good...'
The sensation of rubbing against her vaginal walls was transmitted directly, allowing her to feel the hardness and size of Kazuki's cock more clearly than usual.
'Hmmm... It feels good. But...'
Rias felt both pleasure and frustration simultaneously. And then, at that moment...
Thrust!
"Nnhyaaah!?"
Suddenly thrust deep into the innermost part of her vagina, Rias let out a cry. But the impact was only once. The pace returned to being slow again.
'That was amazing... I want that again...'
The moment she thought that, another impact knocked her pussy.
"Nhaaaaahnnn!"
'Ah, this is it---!!'
Just as she had grown accustomed to the gentle pleasure, a powerful thrust reached deep into her pussy, and Rias shuddered under a lightning bolt of ecstasy.
From then on, Kazuki continued his slow piston motion, interspersing it with deep thrusts at key points, driving Rias to the brink of insanity…