Complex sentence: She has a happy-go-lucky personalty, and often jokes that Willem only likes girls of her age; but she hides her true identity by reading on the real Ithea's diary, as she overtook the real Ithea's body.
Split into simpler sentences: She has a happy-go-lucky personalty, and often jokes that Willem only likes girls of her age. But she hides her true identity by reading on the real Ithea's diary, as she overtook the real Ithea's body.