I just had another thought too, you could actually use pixel depth offset on the opaque geomety to push the pixel depth to be behind the characters. This would not come without issues but it could be possible.
To do it you need to just transform the character position into screen space and then use a circle shaped mask to push the pixels around the character. Or you could use a separate scene capture to capture the shape of the character to a render target and then you could reference that texture in any opaque materials.