The chemistry is the mechanical mechanism by which Hiriluk’s 30-year cherry-blossom-bloom-on-Drum project is achieved. The brilliant pink register suggests a fluorescing/luminescent pigment, not a passive dye — a pyrotechnic-pigment cannonball as the in-fiction mechanism. The Ch. 143 swan song prototype-detonation (Hiriluk’s body bursting in pigment-pink-blossom) demonstrated the how — explosive pigment-release. The Ch. 144 Fairy Dust is the substance. The Ch. 153 cannon-barrage is the delivery system. All three on-page; the chekhov-explicit chain is complete.
Forward-canon: the kingdom’s rename to Sakura Kingdom is structurally cued by this mechanism. The first-blooming-of-cherry-blossoms-on-Drum is the political-coda for the kingdom’s name change.