Other oddities in the battler portraits are a generic woman (two, in fact!), Daigo Dojima, and Juro Horinouchi

None of these can be fought in the final game, and again, don't appear to have any leftovers of a battle with them or that would involve them

Tianyou Zhao has a battler portrait; it's possible he was to be fought at some point in the game's story, just like Nanba, Han & Adachi

It makes sense then that the work they had already put into this character; a naginata wielding bad-ass woman; was then repurposed for the DLC job

Devil Rocker, for what its worth, doesn't appear to be in the same category; this truly does seem like a job that was created solely for a DLC package

Other leftovers include achievement data for maxing out her social link, a leftover weapon, and even an entry for her appearing in the overworld chats, meaning she was potentially cut quite late on

The April Fools release video is the most 'public' way you can see the Ayaka name, as it's used for who would then be known as Saeko

(Most of the stuff in this April Fools video can still be found in both LaD & IW, but that's a thread for another time)