[@Alucroas] If that character won't work for you, I've been developing a fully original character from scratch: A "space priestess" who wields a negative-mass sword using her innate connection to all matter in her vicinity to account for how unintuitively it would move (not to mention telekinesis as a fallback for when chasing it with her hands becomes infeasible). Her fighting style would be partially inspired by the swordfighting aspect of Tai Chi, but of course in space and with the caveat of the feedback loop present in this exotic weapon: "you pull sword -> sword pulls you (which is the same as you pulling the sword due to relativity)".