>>113624395>>113624453The way I see it, it can go two ways.
1) They are very independent, reinventing their strengths and adapting to the situation as needed. She’s the being who most exemplifies “change” beyond a one-time shift among Gems other than Pink herself. Both have a natural sense of humor and desire to make others laugh as well. So they’d go beyond Popeye anatomy and go full-on Looney Tunes, having a more stable body that also can reinvent the physics of the universe as needed. Both are afraid of being passed by or left alone, something that being together solves.
2) They share the same insecurities, both as an extension of Pink’s machinations and callousness. Both have a great deal of simmering anger, and could lash at each other inwards resulting in an unstable monster that would similarly target each being where it hurts; Steven is fully aware of the flaws and pain of each and every named character in the show.
I doubt their Fusion would ever be a villain, but could be an antagonist and leave the cast worse off than the episode began. For example, just breaking them apart wouldn’t fix it if they accused Pearl of raising Steven to be everything she wanted in Rose, making him as much a slave to her will as she was to Pink’s.