福山潤
was once content in following the usual life of a Japanese citizen by attending a university and becoming an office worker, however he is inspired to become a manga artist like his late uncle Nobuhiro. He has a crush on his classmate Miho Azuki that he ends up making a promise to marry her after both of them achieve their dreams. He teams up with Akito Takagi to create a manga that is worthy to be adapted into an anime. The two work under the shared pen name where he serves as the illustrator. His nickname is , which is an alternate reading of the kanji in his name. He is voiced by Jun Fukuyama in the flash web-comic. His favorite manga is "Ashita no Joe". Mashiro is based on the two "Bakuman" authors.