When born in their snowy village far to the north, Akira and his twin brother Yui were the first male yuki-onoko born in a century. While they were treated like princes with every need tended to, they were also prisoners in a guilded cage, their mother dead and their father imprisoned and mad. Akira was weak and a crybaby, always being led around by Yui.
One day they found some supplies left behind by humans, including a magazine that teaches them about life in Tokyo. Fast-forward to the present, Yui is in Tokyo searching for his brother. When a drunk tries to extort him he demonstrates his immensely powerful ice manipulation. Immediately, we’re not quite sure we want this guy to find our kind, gentle Akira!
Unfortunately in an ongoing effort to be more useful, Akira ends up only making more work for Shiki and Kabane. Kon and Aya take the week off so that the focus stays on the core three lads and their dynamic. Akira writes a note and takes off on a jourey to find his brother, taking with him his plushie to which Mihei added AI when he repaired its stuffing. Sure, why not?
There must be some unseen force that draws the twin brothers together, because Akira finds Yui in his first five minutes of his “journey.” Akira buys him a crepe like the kind they saw in that magazine…but Yui doesn’t want it. Akira has shown that despite being a snow boy he’s the warmest of the lads. Even for a yuki-onoko Yui is oddly cold.
Still, when his brother mentions a certain frozen castle from a certain popular American film in which ice plays an important role, Yui instantaneously builds him a massive Japanese-style castle in the middle of a park. It’s a gorgeous and glorious thing, but also very unnerving, because it again demonstrates how powerful Yui is. Then he smashes Akira’s phone and locks him away.
Unaware their princess has been taken captive and locked away in a castle, Shiki and Kabane start clashing immediately in Akira’s absence. Kabane realizes, as Inugami hoped they would, that Akira is the glue that holds their little misfit group together. They decide to go find Akira, and his sole posting of the ice castle helpfully points them in the right direction.
As the post is now trending, a large crowd and even a reporter have arrived to investigate this strange ice castle that appeared out of nowhere. Leaving Inari to the inevitable cover-up, Inugami, Kabane, and Shiki confront Yui, who isn’t really interested in talking. Inugami also notices Yui has a “nullstone” lodged in his heart: basically the opposite of Kabane’s lifestone. which is keeping Yui’s heart well-chilled.
Akira learns that his plushie has Wi-Fi, but only just when Yui returns to tell him the claw-foot bath, four-poster bed and chandelier he requested are ready. Yui leads Akira downstairs, where he learns his brother has also decided to decorate a bit…with Akira’s frozen friends.
It’s pretty clear by now that the strength, precision, and control of his ice manipulation far exceeds Yui’s, and and that Yui isn’t the brother Akira knew, due to that nullstone. But assuming some combination of Kon, Aya, Inari, Nobimaru, and Mihei won’t drop in to save the day, it’ll all be up to our favorite useless scaredy-cat snow boy to set his twin straight and thaw his peeps.