Kain entered his dorm room with a takeout cup conspicuously labelled with the Golden Barrel. He got some strange looks of judgement from classmates along the way. Probably thinking that he doesn't take his rank seriously and is out drinking when they're all training.
However, Bea's skills couldn't be trained in the traditional sense. The best way for her to train is to kill.
Regardless of the looks, Kain jovially looked at his take-away cup. However, instead of drinking the glass as one would expect, he retrieved the Bloom of Ascension from his inventory and placed it in the cup. Replaced the lid and left it on his nightstand.
"Hopefully this works…" The description of the flower's usage did say that it needed to be consumed in its entirety, Kain just hoped that if given enough time, the flower will dissolve in the liquid and achieve a suitable effect.
While Kain waited for the results of his experiment, he had something else to keep him preoccupied.