Soshite Tsuzuki ga Aru no Nara

When the unmotivated editor of a mahjong manga magazine, Sakaguchi, stops at a convenience store in the middle of a business meeting, he is reunited with his senior high school underclassman, Fujishiro. Fujishiro's ability forced Sakaguchi to abandon his dreams of becoming a mangaka, but Fujishiro has stopped writing and is living the life of a part-timer. In order to get Fujishiro to draw manga once more, Sakaguchi meddles in Fujishiro's business. With its novelty, Fujishiro's manga becomes popular, and when he's lured away by a major publishing company, Sakaguchi thinks that that is the end of their relationship.
(Source: Nakama)