As can be seen with this video for breath mints there was a brand of them called SHE HER HER:
And since one of the tie-ins for the single are special Kisumai mints, creatively called Kis-My-Mints, I think it's easy to see that these must be the inspiration for the song. (I have heard the radio rip floating around and I easily think this is their best single song so far and cannot wait to have my copy of the single even though I do need to wait for the album to be released before it will ship out.)
Also to note about the single is that information about what the special promotion it will have with the album has been announced. Those who buy a copy of the single will get an application ticket in them each that can be used to enter a special lottery. Those who win the lottery will be able to attend a special event at one of the upcoming Kisumai concerts in Japan, called Kis-My-Party. Those who buy both single and album can apply for another event that will be scheduled for later and is titled Cho Premium! Secret Event!