On 6 October 2019, the official website of the anime Sword Art Online: Alicization - War of Underworld revealed about the ending theme song "Unlasting" that would be sung by LiSA.[2] The song was released digitally on 21 October 2019, and received a physical release on 11 December 2019 on three edition; Regular edition, Limited edition and Limited anime edition.[1] The single reached number 4 on Oricon, 6 on Japan Hot 100, and 5 on Japan Hot Animation with spent 17, 6 and 12 weeks respectively.[3][4] The song will be featured in her fifth album Leo-Nine.[5]
The music video for "Unlasting" was directed by Kentaro Osawa, and produced by Hiroshi Takayama.[6] The video features a heart-rending story of a breakup between a man and woman in the style of a short dramatic film, with some scene featuring them with rain effect.[7] The video expanded their story from when they were a couple until their breakup. Some scene feature LiSA singing in the room with haze effect. The video ends when both of them part ways.
