I’m Obsessed With the Reverse Harem Male Leads

I won the 1st prize in the lottery and while on my way to claim the prize, I got into an accident and took possession of a reverse harem game! The way to get out of the game is to kill the twin sister, the final villain of the final quest! I wanna go back! I have to return within 1 year to claim my prize! But crazy people keep interfering with the game clearing! Source: NU Includes 7 extra chapters.