Megami Tensei

Are Japanese players ever confused by the number of spinoffs and spinoff sequels present? Or do they memorize them all?

    * Digital Devil Story: Megami Tensei
    * Digital Devil Story: Megami Tensei 2
    * Shin Megami Tensei
    * Shin Megami Tensei II
    * Shin Megami Tensei if...
    * Shin Megami Tensei III: Nocturne
    * Shin Megami Tensei III: Nocturne Maniacs (Director's Cut)
    * Shin Megami Tensei: NINE
    * Shin Megami Tensei Online: IMAGINE
    * Shin Megami Tensei: Digital Devil Saga (Avatar Tuner)
    * Shin Megami Tensei: Digital Devil Saga 2 (Avatar Tuner 2)
    * Devil Summoner
    * Devil Summoner II : Soul Hackers
    * Devil Summoner III : Kuzunoha Raidou
    * Megami Ibunroku Persona
    * Persona 2 Tsumi (Innocent Sin)
    * Persona 2 Batsu (Eternal Punishment)
    * Megami Tensei Gaiden: Last Bible
    * Megami Tensei Gaiden: Last Bible 2
    * Megami Tensei Gaiden: Last Bible 3
    * Majin Tensei
    * Majin Tensei 2: Spiral Nemesis
    * Majin Tensei: Ronde
Giten Megami Tensei Mokushiroku
    * Devil Children: Kuro no Ka / Aka no Ka (Black Book and Red Book)
    * Devil Children: Shiro no Ka (White Book)
    * Devil Children: Hikari no Ka / Yami no Ka (DemiKids: Light and Dark Version)
    * Devil Children: Puzzle de Call
    * Devil Children: Honoo no Ka / Hi no Ka (Ice Book and Fire Book)
    * Devil Children: Messiah-lyzer

You mean like the first Persona?  ouch.