Board Thread:Questions and Answers/@comment-2A02:C7D:B40D:1800:7CAB:12B:468C:2341-20170825192842/@comment-24946616-20170825204624

really, Lost Song is somewhat stand-alone in many cases, sure it assumes you have played Hollow Fragment, as some characters show up from HF. Mechanically, it is quite different. Though, ya can take into account that this, in terms of the story is very VERY much less toned down from the previous game, as is the major drama of the death game is delt with. You could see this as a gaiden game to the hollow series.

Also, if ya happen to like Lost Song, try looking into Millennium Twilight (Accel World vs. Sword Art Online), as it has the mechanics of Lost Song, but also adds in the cast of Accel World (set around 20 or so years in the future of SAO).