Secretly Claimed

【Possessive male lead + a heroine who's both sweet and cool + multiple couples + fast-paced + sweet romance with no angst】 She transmigrated into a book to save him. The System told her that his will to live had to reach one hundred before she could return to the real world. Along the way, she fell for the target of her mission. He's incredibly possessive and kisses her whenever the mood strikes. He's kissed her lips until they're swollen, but she still likes him so much. What is she supposed to do?