Geki! Tokunou! Shiru Mamire ~Senpai ni Dashite Kakete Semen Darake~

The protagonist is a pretty-faced boy.
He’s the kind of kid who radiates “bully me” energy from every pore.
And now, he’s been roped into the “Sabbat Research Club,” or “Saba Ken” for short.

Rinko: “Stop whining and start ejaculating! Today’s goal is five times! We need to draw a pentagram, so get to it!”
The bossy club president, Rinko Aburame, barks orders in her shrill voice. She’s a dangerous girl with a certain goal in mind, working tirelessly day and night on her Sabbat rituals.

Klotho: “Hey, Rinko. You’re being too rough. If you push him too hard, even the last guy we’ve got will run away.”
Klotho Akagashira, a blonde, blue-eyed, buxom foreigner, is blunt and unfriendly—but just as lecherous as Rinko, if not more. Hailing from Greece, she’s now one of the three remaining members of Saba Ken. The boy endures their relentless teasing, clinging to the promise of “initiation” they dangle in front of him.

And what is Rinko’s grand ambition? World domination!
She plans to summon demons and bring the entire world to its knees.

The two dangerous senpais have given the protagonist a powerful stamina booster: “Saikyo Miso.”
This miraculous paste is made by refining an incredible stamina-enhancing vegetable called “Buddha’s Cabbage” into “Monk Water,” then boiling it down into a thick paste.
Under the effects of the miso, the protagonist’s “manly power” goes into overdrive. And in that moment, a mysterious fairy is summoned!

Cham: “Heya! Wassup! I’m Bettigree Cham, the Lower Body Management Fairy! Sorry for the sudden appearance, heehee ♪”
After coercing erotic magic out of the fairy, the two girls transform into magical seductresses!

Rinko: “See this?! With this miracle wonderful magic, we’ll conquer the world!”
Klotho: “Don’t take it personally. You’re just a test subject for our magic. Brace yourself. Yah!”
The protagonist is squeezed, drained, and wrung dry by their magical seduction techniques! Every conceivable form of erotic magic beyond human comprehension is unleashed on his d***.
But he won’t lose. His d***, and the “manly power” within it, will never surrender! Enduring the erotic onslaught from the two magical seductresses, his counterattack begins now!

[Translated from dlsite]