"One of you must marry the princess and teach her a lesson. Her parents agreed with this arrangement.
if one of you can make their daughter fall to one of you. I'll set you all free. But if you fail, I won't gonna do that.
So I'm giving you a mission, make the princess fall to one of you." their father said.
"Ok dad, if we can finish the mission let us be free and do whatever we want" all 9 of them said.
"Fine, just finish this mission" their father said.
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Sorry for the Prolouge :)