'Maybe it was because the Northerners had too much sex. That, or the fact that they were very adept at soul control out of necessity. '
I controlled the soul rivers to move from my heart to my stomach and finally to my dick. They then crossed from my shaft into the Siren's body. Unlike before I learned, I no longer just "threw" the soul river at my partners.
Instead, I sought out their G-spots and rubbed the soul river there. Using {Imaging} I would partially turn my vision to see the insides of my girls. It was like the internal penetration shots that games and hentai loved to do.
Since I had been playing with the Sirens for three days, I already knew the weak points of my girls. So I rolled the soul rivers into balls and rubbed them against the girls' G-spots. I then gently removed the soul layer I had used to nullify the power of the rivers.
The effects were almost instantaneous.
"B-Beloved!.....I-IYYAAAAHHHHH...!!!"