Jeno hates his younger sister because his mother was killed in a hit and run 4 years ago, at that time his younger sister was supposed to be the one who was about to be hit but his mother saved her. Since his mother died, Jeno really hated his younger sister. He never felt sorry when his younger sister was often punished by her father and even beaten because she is required to have good school grades. Jeno enjoys seeing his little sister suffer, he really doesn't care about his little sister.