Answer
Yes, Sunggyu's first musical career debut was as a solo artist. He released his debut album "Just Me" in 2010, and it was a commercial success, selling over 150,000 copies. The album spawned two hit singles, "The Moon" and "It's Alright", which helped Sunggyu to establish himself as a solo artist. He has since released four more studio albums, all of which have been commercially successful.