Hoshino Kasaki loves a good laugh and stirring things up. Her motto in life is [Be happy or die trying]. Despair and sadness are the biggest [mistakes]!
But when Kasaki opens her eyes, she finds herself in the Witch Island prison, facing the threat of a murder every day. How can she let that stand? Hoshino Kasaki realizes she has to get moving, and just then, the System comes online.
[Ding! Congratulations, Host, on awakening the Joy System.]
[You can stir up other people's emotions by causing a scene, accumulate points, and exchange them for "Prank Tricks." ]
Looking over the System's features, Hoshino Kasaki rubs her hands together and gives her roommate, Kinosaki Noah, a mischievous grin.
On the first day, she ties Hiro to a rocket and sends her into the sky. On the second day, she ties Kurobe Nayaka together with a pile of wreckage. On the third day, she plucks the prison warden bald from head to toe.
...Witch Island is thrown into chaos. The witches are furious and itching to get rid of Kasaki, but they can't do a thing about her. As time goes by, though, they change their tune.
Even Nikaido Hiro says, "Causing a scene and playing pranks are wrong! But Hoshino Kasaki... is absolutely right!"
