Constraining bone rotations

Hello,

I have a character who has a cape-like object that hovers around him. The cape is parented to the hips of the character. I would like to constrain it so it moves with him and rotates on the world z (I guess yaw) axis so it rotates with him as he turns. Right now, if he bends his body side-to-side, the cape does too and it is not what I want.

I’ve tried adding a Transform (Modify) Bone tool in an animation blueprint, but I can’t separate the axis so one is fixed and the others pass data through them. I tried get socket rotation in his actor blueprint, but I think I have an infinite loop going on because his cape spins around him.

This character is driven by live motion capture data so I need some rotations to pass through, while constraining one.

I’m new to UE4 and not sure how best to achieve my goal.