Noticed something due to a discussion on multiclass XP penalties linking back to an older thread.

Dragon Devotee (and, IIRC, other PrCs) can grant Sorcerer spellcasting without having any levels in sorcerer. Or regular old Dragons have racial sorcerer spellcasting ability after a certain point in their development.

Battle Sorcerer is a variant class from Unearthed Arcana which decreases spells known and spells per day.

So, yeah, what happens when someone with sorcerer spellcasting that has no levels in Sorcerer takes a level in Battle Sorcerer?