@Xoxo in the side stories Zhenya does become overly jealous of taekjoo, because taekjoo introduces his friend Jungwoo, Zhenya did pull a red flag move, when he was with takejoos mom and he said that the FSB (A federation Zhenya works for, who basically he can get away after killing anybody, like litreally.) were trained in s**(ra**) joking about it, he changed but it was the bare minimum, like for once for example I remember, taekjoo had to leave for a mission, and when he told Zhenya, he totally lost it, and everything. He does Change but it's the bare minimum.