The owner of the Green Drugstore, Kakei, is the one who sends the two boys out on missions, usually without giving them all the details upfront. He seems to know exactly how things will unfold thanks to his precognitive abilities. However, it's noted that this power doesn't work on those more powerful than himself, as evidenced by his inability to locate Tsukiko for Rikuo.
Kakei is a very beautiful person with a gentle and kind demeanor. Nevertheless, he is also quite mysterious, and his expression can shift rapidly from gentle and kind to eerie and potentially dangerous. He has a cruel and even sadistic side to his personality, though this aspect is mostly expressed through subtle teasing.
It turns out that Kakei opened the Drugstore to protect Kazahaya and everyone he cares about.
In the latest chapter of Drug & Drop, Kazahaya tells Kohaku that Kakei and Saiga resemble Hisui and Kokuyo, strongly suggesting that they may be their reincarnations.
(Source: Wikipedia)






