Katen (a Touhou LW original) refers to a sky completely filled with flowers. This is an apt temperament for Youmu, the cyber gardener, from the world delirious with New Year's celebrations. She has retained the same temperament. (Strong against Moon Essence.)

The ability of Youmu Konpaku (B3) from the world delirious with New Year's celebrations (a Touhou LW original). Her ability doesn't seem all that different from the B3 Universe Youmu's. That said, this world has far too many interworld travelers. Youmu isn't good with complex concepts. They're too much for her to handle. This world's Youmu is no different. Youmu finished her cyber-garden work and went New Year's sale shopping with Reisen. Explanation will therefore be provided in her absence. This Youmu comes from a world that is dominated by the Capital through total surveillance. So how could she travel between worlds? Because matters with the Capital have already been resolved in her world. Unfortunately, explaining how they were resolved, and what that resolution looked like, isn't so simple. Youmu from worlds where matters were never resolved would not have left their world, and some Youmus would never cross over into this world even if matters in their worlds were resolved. On the other hand, since matters can be resolved in many different ways, the number of possible B3 Youmus who do arrive in this world is practically limitless. However, this raises a concern. Spacetime is finite, as is the matter within it. This implies that the information capacity tied to a single universe is limited. What would occur if all Youmus were to converge there all at once? Would competition arise over Youmu's ecumenical niche? Or would the universe collapse in an explosive failure? Those scenarios may occur, but it won't happen right away. What happens immediately is far worse. Once a universe is crammed full of information, everything inside it stops moving, in space and in time. Just like a warehouse packed to the brim, where nothing can be rearranged. Would that universe be cold, or would it be hot? Either way, it marks an ending for that world. There would be no change at all, and everything would remain the same forever. Such an outcome is, of course, unacceptable, which is why interworld travel needs proper traffic control. But how can a single universe be kept from becoming completely full? The solution is the consolidation of overlapping information. Similar Youmus share the majority of their destinies. Different Youmus still share a considerable portion of their destinies. Even entirely different Youmus share basic destiny patterns, like names, personalities, and core traits. If destinies are divided into information units and duplicates are merged, the universe's capacity as a gigantic storage device is no longer wasted. This is why individual destinies can diverge and converge, and it's how destinies can be sorted into Star Systems. However, this inevitably destabilizes the sense of self. Each individual's destiny is their own. Each individual's perception is their own. Nevertheless, the framework of infinite parallel worlds rejects this as an entitlement. If the same photo exists in your storage and a stranger's storage, that data will be consolidated whether you want it to be or not. Youmu, who relies on such a frightening mechanism to travel between worlds, has at least learned to adapt to it, even if she does not fully understand it. Shopping with Reisen was fun, and at the same time, tedious. Time and again, she watched Reisen examine similar outfits, fuss over the same things, and reach the same conclusion. "Hmm... this one feels a bit too mature. It might suit my master, though." "You said that already." "This one's a little too flashy. Not really my style... but the Princess might like it." "You're repeating yourself!" "These are way too small overall. Well, I guess they'd fit Tewi just fine." "You're like a broken record." "...Shut it, Youmu. You're being annoying!" Reisen's irritation faded almost as soon as it appeared. When she turned her gaze from the shop window toward Youmu, all she saw was a walking tower of cosmetic boxes. With outstanding balance and a unique intuition, Youmu was able to carry a load far exceeding her own height, even without a clear field of vision. The sight was laughable, but something Reisen was thankful for. She let out a small snort and quickly regained her smile. Needless to say, Youmu noticed none of this.