Spoiler! Masachika and Suou are from same family and masachika is kinda like ayano but not entirely like him, he really got some skill and flexible and for some reason they're parents divorce and masachika blame himself for that if I'm correct that's also why masachika used "Kuze" instead of "Suou" Suou family is kinda rich family and the girl who appear in ep 1 (Dream Scene) is Maria Mikhailovna Kujou (Alya Sister)... since in v4.5 they're talk about past sorry I'm not really good at English and explanation