"Hey...want to make Yurina cum like this?"
Sato-san's seductive words, spoken with glazed eyes, instantly aroused me.
"Ah, wow...Shin-tan's thing is throbbing inside Yurina, pulsing and swelling. You're such a pervert, aren't you?"
"S-sorry about that..."
"It's fine, don't worry. Move however Shin-tan wants."
"B-but people might—"
"Don't worry. I'll try my best to keep quiet."
Sato-san flashed a mischievous smile as she spoke.
I started moving slowly, trying not to stimulate her—or myself—too much.
"Mmm, ah...when you move slowly like this, I can really feel how thick and hard Shin-tan's c○ck is...it's amazing...I can't hold back my voice..."
"H-hey, right after you said you'd keep quiet?!"
"Well, it's your fault for having such a huge d○ck!"
Tears welled in her eyes as she glared at me, making me flinch.
"Hmm, guess they're not here."
"Let's check another lecture hall."
The male students walked away.
"...Nnhaaah!"
Immediately after, Sato-san let out a loud moan.
"Yay, now I can be as loud as I want!"
"No, someone else might come—"
"Don't worry~ You've got a big cock but you're such a scaredy-cat."
She shot me a provocative look.
"Shin-tan, fuck me hard."
"But it's cramped here..."
"Then let's move."
Sato-san pulled me out of her.
"Nngh...wait for me, okay? I'll take care of you again soon."
After kissing my shaft, she headed toward the window at the corner of the lecture hall.
There, she placed both hands against the glass and stuck her ass out toward me.
"Shin-tan, come here♡"
"W-won't people see us?"
"Doesn't that turn you on?"
She looked back at me, teasing.
Unable to resist her gaze, I reluctantly obeyed.
Come to think of it, this might be the first time I've taken her from behind properly.
With Shizuno-san, it's always missionary or cowgirl.
Ah, Shizuno-san's ass is just as amazing as her breasts—maybe I should ask her for this next time.
"Shin-tan."
Hearing my name, I flinched.
"You were thinking about her just now, weren't you?"
"Eh, no, that's not—"
"Well, whatever. Just look at me right now."
Sato-san tempted me, flaunting her voluptuous body without restraint.
At this point, stopping wasn't an option.
Steeling myself, I stood beside Sato-san and touched her slender waist from behind.
"It's fine, just shove it all in."
"O-okay."
I pushed my throbbing length inside her.
"Nngh, aah! So big! Shin-tan's is sooo big!"
Sato-san's moans echoed through the lecture hall.
While nervous about being heard, I was also unbearably turned on.
I let momentum take over and began thrusting.
"Ah, ah! Yes, move your hips rhythmically! Like you're slamming into my ass!"
I kept thrusting mindlessly.
Slap! Slap! Slap! Slap! Slap! Slap!
"So good, Shin-tan! It's making such a nice sound~! I'm getting so excited~!"
Carried away, I roughly grabbed Sato-san's ample breasts.
"Nhyaa! Yes, squeeze them hard!"
Her breasts were large and firm.
Plump and bouncy—different from Shizuno-san's, but just as enticing.
"Thinking about her again, aren't you?"
"S-sorry..."
"Just pretend I'm her and fuck me hard."
Pretend Sato-san is Shizuno-san...
"Shinta-kun, thrust into me as much as you want."
The image of Shizuno-san—elegant yet bewitching—flashed vividly in my mind.
"S-Shizuno-san!"
I slammed into her even harder.
"Nhyaaaah?! W-wait, Shin-tan's suddenly going wild!"
I lost myself completely, thrusting with abandon.
"Ah! Ngh! Haaahn!"
Sato-san's moans grew louder.
"Nngh, ah, aahhn! Shin-tan, I'm—I'm cumming...I'm cumming, I'm cumming, I'm CUMMINGGGGGGGGGG!!"
Throb! Throb!
"Ugh?!"
Before I knew it, I was cumming hard too.
I'd creampied Sato-san deeply.
With one final loud cry, Sato-san arched her back, gazing at the ceiling.
Her supple, tanned body trembled in small spasms.
Still connected, she slumped limply against the window.
"Haa, haa...wow, Shin-tan's semen is sloshing inside Yurina's belly..."
"S-sorry..."
"Don't apologize. And drop the formalities."
"O-okay...ow!"
She flicked my forehead as I turned to her.
"Hey, who was better—me or her?"
"Huh?"
Caught off guard by the sudden question, I hesitated.
"Eh, doesn't matter...but that was the best sex I've ever had. Maybe I should just start dating Shin-tan~"
"Wha—? No, that's—"
As I stammered, she flicked me again.
"Here we go..."
Then, Sato-san pulled my cock out.
A thick stream of my semen dripped from her vagina.
"Yikes, I might get pregnant. You'll take responsibility, right?"
"Uh, well...if you do, I'll take responsibility."
When I answered earnestly, Sato-san burst out laughing.
"Relax, I'm on the pill. Raw sex just feels the best, you know? This is a must if you want to enjoy it properly."
She showed me the pill in her hand as she spoke.
"Ahaha..."
I couldn't deny that she'd dragged me along, but honestly, I'd enjoyed it too.
For a while, I basked in the afterglow.
But then, guilt came crashing down.
"...Shizuno-san, I'm sorry."
I apologized to her, even though she wasn't here.
And, hopelessly, I found myself fantasizing about taking Shizuno-san from behind, pounding into her while admiring her ample ass.