She looks awesome
Arc System Works is developing a follow-up to Guilty Gear Xrd called Revelator, which will add fan favorite Johnny to the cast. But there’s also an additional special mystery character on the way, which is now confirmed as “Jack O.” She’s evidently a goofy fighter on par with Faust.
Based on the scan from Famitsu, it looks like her head will turn into a pumpkin at some point (probably her Overdrive), hence the namesake. I really dig her design.