Pen name used by Japanese manga artist duo consisting of K・かわしま (K. Kawashima) and カラシマヒロユキ (Karashima Hiroyuki, aka. H. Karashima). Because they previously worked as assistants to Urushihara Satoshi, their art style is very similar to his.
Japanese name: かわらじま 晃 or かわらじま コウ (Kawarajima Kou)
Circle name: 片励会 (Henreikai)