Yea , because she's super fucking dense.
Actually she subconsciously does. Her little spirit things were arguing about it in an earlier chapter.
after she meet corn at guam. then her inner demon keep thinking that ren and corn is the same person and they thought kyoko realized it too but kyoko assume that maybe ren has a fairy DNA like corn.. haha. you can read it in this chapter..(づ ̄ ³ ̄)づ http://www.mangago.zone/read-manga/skip_beat/mh/v35/c212.5/pg-3/
I think she is going to cry A LOT and then get all embarrassed.
But I truly wish she slips her tongue and say something like: "I missed you Corn!"