From what i seen most pheromone attacks only happen when they girl heat is at 100. It's easier to just use the Purity Room for all the girls and it will keep their heat from reaching 100. Making it so you don't get any pheromone attacks.
I suggested that we have a room that just decrease their heat but maybe turning it off or maybe a item that just has it so they don't attack you but attack another girl instead would be good too.