What makes Ultra Lover by 2PM notable?

'Ultra Lover' achieved notable commercial success, helping to solidify 2PM's popularity in Japan. The album reflects the group's successful transition into the Japanese market, following their previous chart-topping releases and establishing them as a significant act within the J-pop scene. Released on November 2, 2011, 'Ultra Lover' marked a significant moment for 2PM as they were consolidating their status in the K-pop landscape. This single came after their earlier hits and showcased their evolving sound, aligning with their image as a leading boy band in South Korea during the early 2010s.