WMG / Dog Days

Flonardians have a programmed instinctual desire to love and even obey humans.

Going with the idea that they're Uplifted Animals, some branch of humanity were their Precursors. Hence the original spell treated Cinque as hazardous. (An evil human who knew that a planet almost HAD to love them would be very dangerous.) The spell only summoned children and created the amnesia clause for when the summoned was sent back; so any human smart enough to realize this wouldn't tell anyone else.

• This could almost qualify as Fridge Horror after Dash episode 3. After watching Cinque and Milhi, Becky and Nanami comment that he treats her almost like a pet. And then casually add the fact that they treat their respective rulers the same way. No one involved has any kind of problem with this.
• The original spell also had Geas-esque conditions and muted the effect to some degree. Ricotta removed any and all clauses in the second summoning in season 2; and we're seeing the effect in full force. Hence all the humans having harems; and the Squirrel Princess declaring her love of (and quasi-desire to marry) Becky.
  • Current day Flonardians are not aware of the original conditions; and fortunately even if Cinque and company were to become aware of it; they would not take advantage of it.

Brioche's technique will turn Cinque immortal.

The same way she is; ie long-lived, once he masters it.

• Afraid not. In the third series it's revealed that Brioche and Isuka are immortal because they were splashed with the blood of a demon they killed.

Cinque will somehow send Ricotta cellphones if he gets back to Japan

• They somehow communicated when and where the portal would be enough that he was able to plan for it and bring Becky along.
  • Actually, Tatsumaki has been delivering letters back and forth, interdimensional mail.

Cinque will be returned home after Biscotti manages to contact the Time-Space Adminstration Bureau and they transport him back to Non-Administrated World #97

Flonyard is a colony of permanently Uplifted Familiars.

In the long ago past; some Familiars gained enough power in their own Linker Cores that they became able to exist without a Contract. (There are triggers that temporarily result in them taking their non-humanoid forms.) Not wanting masters, but viewed as disruptive to other worlds; they were given Flonyard. For the most part; this planet was left to its own devices, although there was one incident in the almost as long ago past where the TSAB had to step in and Administrated the hell out of them to prevent them from using conventional warfare. The natives viewed the TSAB as gods and followed the "non-fatal warfare" doctrine with such gusto that the TSAB never had to intervene again.

Leonmichelle is repeatedly invading in order to toughen up Millhiore in preparation of some imminent Big Bad or other calamity.

Supported in episode 6, where the Millhiorans suspect that monsters are becoming a problem in her area.

• This is actually the case for the War System in general; in case the Divine Protection fails against the demons.

Leonmichelle's vision is a Self-Fulfilling Prophecy

Tied to the WMG above, the Biscotti lost the bet and were obliged to hand over the swords. The blades, being artifact intelligent weapons took it as treason, possessed their wielders and turned them on each other.

• Note that the palace is under protection, so it would presumably take a strong magical weapon to injure, not to mention kill, someone there.
• While not exactly how you described it but By the end of episode 9, it seems the prophecy really is self-fulfilling, at least the part about the floating platform.
  • It is self-fulfilling, but it's obviously shown that Leonmichelle's stargazing ability is not set in stone. Screw Destiny indeed.

Brioche was a summoned hero

Her conversation with Laurent at the end of episode six, implies she's not from Biscotti originally.

• Related Guess: Yukikaze was royalty for a now defunct kingdom and was the one who summoned Brioche.
• Another Related Guess: Sending a hero home requires that they duel another summoned hero and survive, leading Cinque to fight, and defeat, Brioche. A possible outcome of this mirrors the next wild guess.
• Seemingly refuted in Episode 9, when we see what appears to be a young Brioche standing in the middle of a wrecked village.
  • Jossed. Her family was killed by demons so unlikely that she was from some other world.
    • She is, however, "different" in that she's over 150 years old; has gods call her "Master" and doesn't explain why for either.

The big bad (if there is one) will be beaten by the Galette's sacred sword Ex-Machina.

• Episode 10 suggests that two other swords were involved, instead.

Cinque will save the day in a manner that somehow strips several of the main female characters naked.

• Well, one, sort of...
  • he finally did it in Dash (with Gaul's help), though the stripping part was actually Yukikaze's fault.

Despite what Millhiore thought, Cinque will not be able to return to Flonyard after he is sent back home.

• That note Ricotta received in Episode 11 made her sad for some reason and the title for the next episode, "The 4 Conditions", is pretty suggestive as well.
  • Confirmed but also takes away everything he got from his time there, even his memories.
    • Which makes the lyrics for the ending theme a little more sad, if you consider who is singing it.
  • Jossed and Confirmed both at the same time. To explain, Cinque does "lose" his memories. However, it's revealed that if Cinque had told at least 3 people he would return, gave one person a possession of his(preferably from his world) and told one person in writing that he will return, then he is allowed to be resummoned.

There will be a crossover since Cinque is actually Takuto warped into an Non Administered World

• Notice how the world they are in seems to have a similar style that appeared in another prominent Seven Arcs anime? And how the world produces Non-Lethal K.O. magic similar to that anime? How the princess of Biscotti looks a lot like some other prominent loli mage?....

Nanami will become a Summoned Hero for Gallette

• Cinque & Nanami's friendly rivalry was a background element during the series / first season. Thus if Cinque does bring Nanami & Becky with him to Flonyard, it wouldn't be a stretch at all to see Nanami enlist with Galette while Cinque joined with Biscotti just so they could compete. That, or Nanami could simply just be a cat person.
• This actually seems very likely.
• Pretty much confirmed in the latest trailer for the second season.
• Definitely Confirmed at the end of the first episode of season 2

Millhiore will participate in the battle in episode 3 of season 2

When they were ready to start the afternoon session, Millhiore was all suited up in her armor when she was previously wearing her usual dress. She only wore armor once in season 1 When she intended to fight Leonmichelle at the tail end of the season so Millhiore putting on her armor means she's planning to fight.

• Confirmed, turned out to be single salvo battle between her and Becky.

Warring parties in Flonyard regularly practice Kayfabe

Gaul calling Shinku stupid while he and Genoise were cutting a promo at the start of season 2 seemed odd since Gaul had apparently gained a measure of respect for Shinku by the end of season 1. Then in the next episode, Becky's "kidnapping" looked like it and the 3-way combat setup had been prearranged during the lunchbreak and note that Becky didn't resist or yell at all when she was picked up and carried to the floating terrace. The reason they didn't do it in season 1 was because Leonmichelle was being unusually serious about things.

The current history of Pastiage is souped up

It happens a lot with many of the unwritten legend about one's ancestor. Supposedly, even the Demon King might not be THAT evil. It was clearly mentioned that war in the past is not for fun, which gave us the possibilities of Gray-and-Gray Morality or White-and-Grey Morality aside from the usual flat out Black-and-White Morality. And the Hero King is a woman which surprise everyone.

• Not only that, but apparently the trapped and secured treasury of the royal family that's sitting right under the Pastiage's palace... Was apparently Calvados' "final boss" lair during his stint as Demon King. Given Couvert's pecularities, one has to wonder if Hero-King Adelaide is the only important-past-personage-now-freed-into-the-present the country's royalty is descended from.

Cinque and Couvert are both distantly related through Adelaide

Given how there was no reaction to the expected combination — a direct descendant of the royal family (Couvert) and her summoned Hero (Becky) — so obviously the information passed on through the Royal family of Pastiage was distorted by time. So why did the monument react only to Cinque? And why was it when Adelaide was reawakened, (depending on the translation) the automated "system" message mentioned descendants? Plural.

This means that while Couvert got half the requirements right during her first tries, she was able to unlock the monument with Cinque because she also got the real second requirement (through trial and error) — a Hero who was also descended from the Hero King. The only weakness to this theory is, of course, the fact that the monument didn't recognize Nanami, who as far as we know is Cinque's first cousin.

• Maybe that's because Nanami is from the other side of the family

The last episode of Dash will be a Cliffhanger Sudden Downer Ending

Cinque, Becky and Nanami return to their own world...and find they just missed the apocalypse.

Okay, so this probably goes under Poison Oak Epileptic Trees

• Obviously jossed as of the last episode of Dash. Everyone returns to their lives on Earth, but with a promise to return after Cinque and Becky's Fall examinations.

Mercurius rebuilt Becky to make her worthy to be a hero

And that's why we saw her amazing (and strange) henshin deck, which was never repeated. Afterwards she's a lot different, more sure of herself, more forceful, and she has a lot of control over her magical power.

Valerie and Adelaide are married.

And Couverte is descended from them both.

• Almost confirmed: it's not stated 100% clear yet but as of Double Dash ep.8 they said couple of times that current Pastillage dynasty are their descendants.

Adelaide has a demon stone.

And it's on all the time. That's why she's so strong, and why her eyes are stars.

• When Rebecca activated her demon stone, her eyes changed to be stars. But that went away when she turned it off again. Adelaide's eyes have always been like that, and it must be because of a demon stone. As an even wilder guess, it's the stone that's in her crown.

I think Sharl is a tochigami.

Farine says that she herself is a tochigami (land god) just like Yukikaze, and I suspect that Sharl is, too. Which probably means she's a lot older than she looks.