What makes Sleep by SID notable?

'Sleep' reached notable commercial success, peaking at number 8 on the Oricon Albums Chart in Japan. The album's unique sound and lyrical depth resonated with fans, leading to critical acclaim and establishing SID as a key player in the alternative rock genre within Japan. Released on March 3, 2010, 'Sleep' marks SID's first album since their rise to fame with their 2008 hit single 'Monochrome.' By this point in their career, they had solidified their status in the Japanese rock scene, transitioning from underground success to mainstream popularity, particularly in the anime and visual kei communities.