Todd Spangler NY Digital EditorSerialized fiction app Radish is being acquired by Kakao Entertainment, the entertainment arm of Korean internet giant Kakao, in a transaction valued at $440 million.Word of the deal comes as South Korea’s Naver on Monday announced the completion of its $600 million-plus takeover of Wattpad, a user-fiction story app.Radish’s board of directors and a majority of its shareholders have approved the acquisition, which is expected to close in June.