[Tamaki-Kun]

Needs more details, such as your youkai setup, how many youkai slots you have, etc. It won't apply if any of the three dragons aren't in your active slots, for example.

The three dragons are in my active slots, yeah. I have seven Youkai slots, with Hatsu, Haku, Chun, Phase Python, Sazae Oni, and Seiryu as Shapeshifter/Magic Gunner. I have other Youkai that aren't in the active slot due to lack of faith stat. 

I did the test shifting Haku into the inactive slot, getting into a fight, installing to check my stats, then repeating but with all three dragons in the active slot.

I just immediately install Seiryu at the start of the fight. Daisangen doesn't apply the bonus stats it should be giving.