ATF (all time favs)

Yu Ijin was the sole survivor of a plane crash when he was little. After becoming a mercenary to survive for 10 years, he returns to his family in his hometown.

The existence of the second child, Karina, who was the successor's youngest twin and the one who wasn't as competent as her sibling, has been concealed by the people around her all her life.One day, she finds out that she only has one year left to li