Sakura Santa/Headscratchers

Itsumi Route
""My entire life up until that point had been spent with [Itsumi]. It's a surreal thought when you think about it. Bonds just don't fade. You might forget about someone, or not quite remember their face... But when you meet them again, it all comes back to you.""
 * If Itsumi means so much as a childhood friend to Koji, then why didn't he remember her when he was with the other girls (in separate continuities)?
 * Koji's thoughts indirectly provide an explanation in her route:


 * During their first date, Itsumi wonders if Santa (she's thinking of the typical character) knew what she wished for this year. Koji acknowledges her, by referring to Santa as a "he"... Except he knew Santa was a "she"! He met her in person!
 * And no, Koji wasn't hiding his meeting with the mythical figure to Itsumi, because he doesn't say or think anything about the matter.
 * A detail in Santa's route clears the ambiguity. On her workshop, Santa explains to Koji that there are many, many members of her family and that they are all tasked with different parts of the world for the Family Business. This explains a hole in the typical Santa Claus theory. The point is, Santa Claus (the big guy with the white beard) does exist, he's just Miss Claus's father, and Miss Claus is just a member of the business.
 * It still doesn't explain why Koji didn't think about his meeting at the date. Also, Koji (from the Itusmi continuity) doesn't know that, as he only learns the fact if he waits on his apartment for Santa on the first day. That hasn't happened because he spent all of his time with Itsumi.
 * To answer the question, Santa couldn't have known what Itsumi wished for, since Itsumi is an adult. Santa, as witnessed by Koji, can read children's hearts, but only children's, as she had to ask Koji for his wish.
 * Here's a clarification: In the Harem Route, Santa meets Itsumi and recognises her from her memories. Later in the conversation, Santa mentions to her, in an effort to prove her existence, that she left Itsumi "that princess doll you always wanted." That was in reference to the past. Nothing Santa said was meant to mention the present.

Santa Route

 * Why was Santa so OOT in the ending? She's so suddenly introspective and collected. I mean, she was supposed to be bumbly and anxious about herself...? I know Christmas was saved because she believed in herself (and her dad helped too), but then she acts like two completely different people...

Harem Route

 * For a person who has just witnessed the mythical figure of her childhood, Itsumi sure doesn't give a crap about that. Rather, she instantly names Santa her "rival".
 * Itsumi's got her priorities, and her romance with Koji is in danger! (gasp)