Took Taro was afraid that if his characters didn't stand out enough, that Drakengard wouldn't stand out, leading to many adult themes and faults in the main cast.
Ending A doesn't directly lead into Drakengard 2, but is almost the same. Even though Caim never met Seere in this timeline, Seere is a prominent figure in Drakengard 2.
In the game's first timeline branch, Inuart flies off with Furiae's corpse and their fate is ambiguous. This is resolved in Drakengard 2.
Series creator Yoko Taro designed the game plot with the idea that Furiae would never live and be rescued because he loathed the little sister princess trope.
Caim and Angelus (the red dragon) form an emotional romantic relationship by the end of Branch A.
Many of Drakengard's more adult themes were diminished in editions outside Japan. This includes Leonard's pedophilia and his life mission of redemption, and Furiae's incestuous feelings for her brother Caim which leads to her committing suicide,