Uzaki-Chan Wants to be your Sex Girlfriend

A lonely, overweight, bald adult NEET lives a repetitive, empty life of endless gaming, junk food, and isolation. His only source of real emotion comes from playing online games with the only online friend he has.
One ordinary day, that online friend suddenly appears at his door! And it turns out that all this time his online friend was (grasp) a woman! It’s Uzaki Hana, and she wants to hang out!

Tonight, I'm gonna get my friend to fuck my girlfriend...
Akitoshi, a cuck at heart, wants to see his straight-laced, art student girlfriend Minatsu get fucked by another man no matter what!!
He can't hold back the desire.

Upon discussing this with his childhood friend, Haruki...
Haruki: “Got it.”
Haruki: “So you want me to fuck Minatsu-chan?”
Akitoshi: “Yeah. I'm begging you.”
Haruki: “For real? Like, are you serious?”
Akitoshi: “I’m always serious.”
Haruki: "You... you're outta your mind..."
And so, after the three of them had dinner, the two idiots tried their best to get her in the mood.

Chiyo Tochikura, an ordinary high school girl with slightly large breasts.
The day after experiencing a thrilling first time with her wonderful boyfriend, she gets drunk at a welcome party at her part-time job and is taken home by a senior.
Threatened by a sleazy freeter, her body is used as he pleases…
Can this big-breasted high school girl protect her pure love?! (She can’t.)

Aoyagi Yoshino wanted to be a pianist when she was young, but she couldn't achieve that dream. Now, she's the president of a company, is married and has a daughter.

Her daughter has talent with the piano too, so Yoshino wants her to become a pianist and achieve the dream that she couldn't. Everything was fine until her daughter got a boyfriend.

Yoshino thinks that having a boyfriend is gonna make her daughter not want to study abroad and her piano dream will fail again. So, Yoshino decides to seduce her daughter's boyfriend in order to make him break up with her.

Regina in a certain village feels worried when she is the last girl
remaining single left by other girls getting married one by one,

She feels, like, totally worried.

Regina:
"It's too bad...... I'll remain single for the rest of my life."
"It's unacceptable! I must find a good guy and get married!"

As soon as she gets ready to go out, she rushes out of the village.

Regina:
"Nothing is more fearful than being 'forever alone'! I'll prove how a woman is strong!"