The subject of the trope will physically grow larger then normal proportions, this can happen slowly or very quickly with the most common areas to grow being erotic or sexualized areas for example breasts, asses, penises, muscles and full body growth. There isn’t an upper limit on the extent of the expansion unless stated. Subjects of this trope can have breasts larger then known bra sizes through to room sized to city and geographical location sized. The same is true for the previously mentioned erotic areas that can grow or fill body growth. The default emotions of the subject are to find the changes erotic and sexy leading to a heightened sex drive and need to fuck those around them.