It was supposed to be a love simulation, so why are they also players?

It was the first time I had a girl I liked, and the first time I loaded a simulator. These two happy events coincided with each other, and the time I got should have been as happy as a dream...
But why did it turn out like this?
Xia Mu, who escaped from Shimokitazawa Mental Hospital, was at a loss as to what to do with his sister.
Bond Simulator (×)
Dating Simulator (✓)
"Nagasaki Suyo, I love you. My brain, my heart, every organ in my body is saying, I love you! Please marry me quickly!"
"Toyokawa Shoko, are you willing to have a love affair with me that will last forever, with marriage as the prerequisite?"
"Ichichi Hongxia, I like you because of love."
"Jing Qinrencai, I like you, quack! Stop elbowing me!"
"Aoyama Nanami, I like you, huh? Why are you asking who's more important, Mashiro or you?"
and many more!
Why did they load the simulator too?
Xia Mu, who was pushed down, realized something was wrong, but it was too late.
"Quack! Sushi, save me!"