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Kimi no Mana wa Rina Witch

At Witch School, girls are educated to make the best "mana supply" (sperm).
Sex is not any mere leisure activity, nor is it a brutal affair.
Students are arranged in boy-girl pairs to make sure a consistent supply.
Mana enhances a Witch's powers so she'll battle the Eaters!
It's in everyone's interest that master all kinds of sex technique.
More pleasure, better mana. Better mana, stronger Witch!
* Boys give the mana, girls absorb it most people are manboobs
Are you going to choose Rina or Alyssa? While living school life choices will arise
which affect sex scenes and also the ultimate route with one heroine or the other.
Flourish and you'll obtain a happy end. But with who? That options are yours.