It's a self Buffer, that's the worst kind of Kamihime to be honest.
I dont want to discourage you or anything but that's one of the only "bad" water SSR alongside Ea, Poseidon and Shiva
Regardless it's better than most SR's just for raw damage and hit increasing Burst Bar goes well with Shingen, there's always a workaround to make this "weak" Kamihime work and actually be really helpful to your engine.