Like the monster stove behind her.
Never seen a guitar like that before, just ones with more guitar necks.
Beats having to detune strings to play some classical stuff, you have the extra notes right there.
It must be a one-off.
Years back, I went to the Guitars: The Instrument That Rocked The World exhibition. They had some really interesting stringed instruments including harp guitars and harp mandolins. Very cool instruments!