Umm. no, Not so quick.
It took a while to select and separate Kylie Jenner's head for additional mangling. I did it with the lasso tool, then the magic wand to select unwanted areas for deletion. There was some zooming later on, around the neck area.
Then I selected her head and inverted the selection to everything NOT her head and deleted that.
But the majority of the (long) time was spent trying to use the lasso tool with a track pad. Here's a tip: don't.
As you can see, Picard's thumb is destroyed - maybe he got it caught in the replicator? Maybe I didn't know how to shrink Kylie's disembodied head to Picard's body size.
I noticed later that doMima avoided this issue by rotating Kylie's head to the right... avoiding the thumb and allowing the Captain's 4 dots (pips?) to show on his outfit.
Now I know what to look out for. But I'd had enough for one session.
Next time I will try the eraser, as you'd mentioned.
Btw, thank you again for suggesting the software. I like it! :-)