With Gabriel promising to return tomorrow, Maou and his generals and frenemies adopt a fortress mentality, sending the normal human Chiho off while Ashiya and Urushihara stay on stanby at Suzuno’s. That leaves Maou and Emi together with Alas Ramus at his place.
While Emi is weary of this arrangement, and can’t commit to allying herself with the devil, she will do what it takes to keep Alas out of harm’s way, so in that regard her and Maou’s interests are aligned. When they turn in for the night, Alas makes sure to grab both of them close.
While initially uncomfortable with the proximity, Maou and Emi bask in their “daughter’s” unbridled love and exuberance, while Emi is genuinely moved by Maou’s bittersweet improvised tale of a traveler who became a king.
Emi gets a literal rude awakening around 5:00 in the morning from Gabriel, who was simply lying in the room waiting for them to wake up (ambushing a sleeping couple is beneath him). Gabriel continues to be a paragon of reasonableness, but makes it quite clear: he’s leaving with either Emi’s sword or Alas Ramus.
We learned from further explanation form Suzuno earlier that as the Guardian Angel of the sephira Yesod of the Tree of Life, Gabriel has a claim to both sword and Alas, as they are shards of Yesod. But that doesn’t matter to Maou, who planted and nurtured the seed that became the apple that became his near-as-makes-no-difference daughter.
When saved from death and reborn (you can see himself in his bedtime story), Alas was a symbol of hope he gained, so Maou offers his head in exchange for letting Alas at least stay with Emi. Gabriel laughs at Maou and Emi in marital synch one minute, and is choking out Maou the next. He’s out of patience.
But while Emi’s sword can’t do much against Gabriel, and Maou is far to weak to stand against him, Alas is more than up to the task. All it takes is hurting her Papa to send her glowing with rage and blasting out the side of the wall, taking ol’ Gabe for a violent aerial tour of the city at near-dawn.
Emi gives chase, and when she gets her sword shattered by Gabriel, Alas backs her up—as long as Emi tells her she and Papa will be together with her forever. After Urushihara cows Gabe’s Angel guards with the sheer power of his former archangel status, Suzuno takes Maou on a ride to where Emi and Alas are an unceremoniously lobs him at Gabriel.
While grabbing and restraining Gabe, Maou tells Emi to hurry up and kill the two of them, something Emi isn’t going to do even without Alas being right there watching. So Gabe shakes free, leaving Maou to fall. No one can get to him to stop his fall…except for Alas.
Emi then whips out a fresh sword and her armor (complete with a partial maho onna-kishi transformation sequence) to warn Gabriel to get lost, even managing to slice his cheek and make him bleed. But before he goes, he makes it a point to admonish Emi and tell her to reflect on “what sort of being she is”.
Emi returns to earth exhausted but none the worse for wear, but the damage is done: Alas is gone. After saving Maou, she said she wanted to be with them forever she’d have to say goodbye “for now”. Maou is devastated, but as Chiho learns while having coffee with Emi, by “for now” Alas meant only for a short while, as she has now fused with Emi’s sacred sword (now a dagger).
Emi presents Chiho with her very unique predicament of wanting to defeat the Devil King someday, but not being able to do it with a weapon that’s also his child! Emi’s fine with that; she’d rather Maou and Emi simply continue to get along, even if watching them grow kinda-sorta closer thanks to Alas leaves her out in the cold romance-wise.
Alas also insists Emi not let Papa suffer longer than he needs to, and has them reunited that evening. To Emi’s surprise, seeing Alas again actually brings tears to Maou’s eyes; Chi-sis explains to Alas that people also cry when they’re happy.
We find out that Gabe told Emi he hoped she’d prioritize the world’s safety, and then learn that Lailah, Emi’s mother, was the one stole Yesod in the first place. Could Emi’s mom be the woman who saved Maou’s life? There’s a lot of intrigue (and potential dread) on the horizon, but Alas wielding her innate power has at least bought this little pop-up family a little more time to be happy.