zenitsu is a worried guy only if he seems unknow people but only if he sees nezuko he falls in love with her ever time he sees her while nezuko not knows that zenitsu loves her that much.and zenitsu is walking around in the hashira house until he hears shower noises..and he thinks "what if it is nezuko".and he stands right before the door of the bathroom now while blushing and thinking that nezuko might be in there