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A story about turning a frigid girlfriend into a lewd and sensitive woman.

Haruna, a hardworking but slightly natural girlfriend whom he met in college and has been dating for two years.
At first glance, they seem like a normal couple, but the guy has a problem: "My girlfriend is frigid and I can't have satisfying sex -!!"
He consults with his friends Sota and Chika, and they find out that they have a lot in common in terms of creating atmosphere and getting to know each other well.
When he asks his friends, Sota and Chika, for advice, they tell him that the secret to improving sex is to create the right atmosphere and get to know each other well.
Will you be able to make her cum successfully?