User blog comment:Crimson and Darkness/Shin DxD 3 discussion/@comment-82.160.23.173-20191223201551/@comment-10330822-20200128045316

You guys also think perhaps that Ryuuteimaru is just supposed to be a place holder form a normal dragonification AxA form?

I was just thinking. Issei and Ryuuteimaru are connected through their familiar pact, and it was stated that Issei's aura actively affects Ryuuteimaru's development and evolution. So when it became a medium for Great Red's power, I was curious is it was more because Issei himself can't manage it at his current size, and a dragon Issei could.

AxA also is theoretically, below Balance Breaker and Cardinal Crimson based on the whole AxA, BxB, and CxC. Concept, which caused me to think that AxA was something Issei can use entirely without Boosted Gear and hence why BxB is considered "above" it, because you could stack its effect on stop of AxA. So he uses AxA normally, and then stacks the BxB/CxC/DxD armors on top to achieve his fully power, and this form is in turn fueled by the ExE, the Eros Engine.