[Apologies for changing the trope. The main text is in third person.]
You're a homebody with practically no experience of romance. One day, you're suddenly bound to a System and made the heroine of an otome game, taking part in its romance scenarios: dating athletic boys.
You: "I refuse!"
The System confiscates the things you love and forcefully creates all kinds of romantic situations between you and the athletic boys.
You simply step outside, only to be knocked down by Hinata, who's riding a bicycle that's out of control. The boy rushes over to you in a panic.
The System laughs smugly: [Next comes the romantic bridal carry.]
You are horrified. You leap up, scoop Hinata into your arms, and sprint all the way to the hospital with him.
The System: ?
Hinata, blushing: It's true that we have to take care of our bodies when we play, but is Yuri a little too worried about me?
Tanaka and Nishinoya, who happen to see it: ?
*
The System traps you and Kageyama in a couples' hotel room. In the dim lighting, every surface is covered with suggestive, unspeakable things, and the temperature keeps rising.
Seeing that things are taking a bad turn, you rummage through the pile of adult toys and find something you can at least make use of. "Kageyama, let's do something more fun."
Then, as the boy's face grows redder and redder, you get into a setting position and invite him, expressionless, to play volleyball all night.
The System: ?
Kageyama: ...
*
While Oikawa is receiving gifts from his fan club, a bouquet suddenly appears in your hands, and a banner reading "Lord Oikawa Is Number One" hangs above your head.
The moment your eyes meet Oikawa's, a chill runs down your spine. The System trips you as you try to run, sending you tumbling toward him. Just as you're about to pull off the grand feat of kissing him, you lunge like a starving tiger and shove the flowers straight into his mouth.
Then you change the banner to read "Lord Kageyama Is Number One" and tell him, "I've stopped being your fan."
The System: ?
Oikawa: ? Well done, young lady. You've successfully caught my attention.
You make it your mission to ruin every flirtatious situation and teach the System a lesson. But thanks to the System's behind-the-scenes meddling, your grandfather, a volleyball coach, transfers you to his school.
You become the manager of Nekoma's volleyball team. Training camps, practice matches, tournaments...
Not only have you failed to escape the athletic boys, but there are even more of them around you now!
You will never bow to the forces of evil!
You firmly believe that after all your ridiculous antics, no one will want to date you!
And then they confess to you.
#Inspired by Romantic Killer
#OOC warning, everyone dotes on the heroine
Theme: A life filled with sunshine and love