The answer is clearly to send Ami a puzzle.
I'm favoring literal nonsense coded to look like a puzzle, leaving Ami to either (A) think she has overlooked something, (B) think Hazou made an error with the coding and will try to work even harder to find it and point it out to Hazou, or (C) recognize it as nonsense.
Either way, Hazou gets his rival/love interest.
To avoid complete embarrassment from (C), I propose a very very simple and short code hidden in the middle of the nonsense.
Step 1) Have Hazou-the-character realize Ami is a plurality
Step 2) write a meaningful letter about how we accept her as she is, and that we look forward to learning more about her as time goes on. Maybe even reference the hair braiding moment for additional wholesomeness. Have the letter be stupidly earnest in the way that only Hazou can be.
Step 3) use a coded cypher, wherein each character/word (whatever the MfD native language uses) is replaced by a code
number that directs the codebreaker to a book (maybe a published anthology of Minato's poetry). So the word "Hello" would look something like (4.38.8 as in "poem 4. Line 38. Word 8"). Without knowing what book Hazou is using (and we
wouldn't be telling her), Ami would have to be accurately model Hazou's nature well enough to find out what book(s) he's using as a "base."
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We could be cheeky and use that one Analysis of Yagura's My Vision (the one that interprets sexual congress to occur during the fifth date rather than the third, compounding the fact that Hazou-pilot wants to take things slowly --something Ami has teased us about before).
We could use the bog-standard WoF as a way to celebrate Ami's renationalization.
We could use Minato's poetry to express the empathy Hazou-pilot feels for Minato's character, and a self-aware nod to the fact that (much how Minato is bad at poetry...) Hazou is bad at cyphers, but is trying anyway in an attempt to connect with Ami on a greater level.
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Random thought: we could do all 3 as a way of communicating all of that at once. It would appeal to Ami's mentality of "every singular action has more than one reason/goal/end."
We could make the cypher something like "1.4.38.8." so it would be "Minato's Anthology. Fourth Poem. Line 38. Word 8." And then when we switch to the next book as a cypher, it would be "Next Book/WoF Doctrine. Chapter number. Line number. Word number."
If we
really want to be subtle (which I say we should be, for maximum trolling), we could have Hazou play around with which parts of the letter are cyphered by which book. Because that would add a layer of nuance that would tie Ami's brain into knots.
"Hazou cyphered the sentence 'I look forward to knowing you all better, if you are all comfortable with such a thing' using [That One Interpretation of Yagura's My Vision]. Is he compounding that conditional 'if we're okay with that' by cyphering it in
that material, or is he opening the door to an officially romantic relationship, but is also re-emphasizing his already-known desire to take romance slowly?"
If Hazou cyphers that same sentence with Minato's Anthology, is Hazou doubling down on the earnestness and self-aware amusement (Minato wasn't very good at poetry, Hazou isn't very good at cyphers) as a sort of in-joke, or is Hazou trying to borrow the connotative feeling that
that specific Minato Poem has to emphasize his acceptance of the Ami System?
[Edit: We can have so much fun with this and turn the game on Ami for once! ^.^]
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@Velorien, does this idea interest you
[as in, would you be interested in writing such a thing]? Is there any way I could bribe you into hinting what Ami's reaction may be to such a gesture from Hazou?
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Edit: use Earthshaping to encode the puzzle into a quartz tablet? Earthshaping is a noncombat jutsu (symbolism of olive branch/desire for a peaceful or cooperative relationship, but the puzzle itself maintains their mutual game of tag/one-upsmanship?) and the quartz created/shaped by a noncombat jutsu shows the value in cooperative/peaceful dynamics? Adds an additional layer for Ami to poke for.