Even among other visual novels, these games are so radically different that almost nothing else can be considered like them, even if similarities are there. (hardcoregaming101.net)
Investigating and solving mysteries is more involved than the gameplay in other visual novels (playstationlifestyle.net)
A major feature of the series that tends to set it apart from other visual novels, other than its relatively mature content, is the use of branching paths and multiple endings, all of which must be experienced to unlock a final, true ending. (nintendowire.com)