Mr. Simple (2011)

• Mr. Simple
• Opera (오페라)
• Be My Girl (라라라라; Lalalala)
• Walkin'
• Storm (폭풍; Pokpung)
• Good Friends (어느새 우린; Eoneusae Urin)
• Feels Good (결투; Gyeoltu)
• Memories (기억을 따라; Gieogeul Ttara)
• Sunflower (해바라기; Haebaragi)
• White Christmas (엉뚱한 상상; Eongttunghan Sangsang)
• Y
• My Love, My Kiss, My Heart
• Perfection (태완미; Taewanmi) (Bonus Track)
• Superman ("A-Cha" Bonus Track)
• A-Cha ("A-Cha" Bonus Track)
• Oops! ("A-Cha" Bonus Track)
• A Day (하루에; Harue) ("A-Cha" Bonus Track)
• Andante (안단테) ("A-Cha" Bonus Track)