Yes, Goro-chan (Inagaki Goro) is left-handed. He has mentioned it several times himself and has been shown to write or do things left-handed in his dramas.
GORO
Goro Hayashibe was born in 1976.
Goro Tameike was born on 1964-03-28.
Goro Azumaya died on 2010-07-08.
Yes.
Goro Inagaki was born on 1973-12-08.
SMAP is a famous Japanese group that makes songs.
Seiji Inagaki was born in 1973.
Jitsuo Inagaki was born in 1928.
Jitsuo Inagaki died in 2009.
Yes, he is lefthanded.
He is most likely to be lefthanded.
Junichi Inagaki was born on 1953-07-09.
Inagaki Manjirō was born on 1861-09-26.
Inagaki Manjirō died on 1908-09-26.
Hiroyuki Inagaki was born on 1970-04-24.
Hiroshi Inagaki was born on 1905-12-30.