With the increase in herbivorous men in society, the syndrome of wanting women to put on condoms during sex is widespread. Girls who are devoted to these passive men have no choice but to ask their closest male brothers to help them practice putting condoms on with their mouths. Even if they are brother and sister, if they are asked to do something like that, it's impossible not to want to do it... The same goes for sisters, who end up doing it in five consecutive incestuous acts!