Hmmm lets see...
1) she doesn't wear a mask to cover her face and hide her identity.
2) her MG full name is Magical Girl Patisser Kosaki chan. And
3) she keeps calling raku "ichijou sempai" every time they meet.
Hmmmm.....a bit late on the uptake but seems this version of raku is less dense than the original (nisekoi version)
Now the denser ones are the sisters who can't seem to realize who the other is even when they have their names on their costumes or the MG name...