MIDE-051 _Fucking a girl who is obedient but secretly sexually explicit

After a few years of going to Tokyo to study at university, my younger sister took advantage of the New Year to return home to visit her family. I never expected that after not seeing each other for a long time, my little sister had become a beautiful, graceful young woman, but... I couldn't believe my eyes, my sister now no longer had the innocence like before, but instead had something very feminine, very lustful; This is clearly shown in the way she dresses (skirt is too high, underwear is clearly visible, shirt is very thin, big and firm breasts are clearly visible). The thought of incest always appears in my mind every time I see her. What should I do???