He's the current weapon of the Shinigami and Maka's father. Spirit is intensely protective of his daughter—constantly ready to rush in whenever she needs help, though the Shinigami usually stops him before he can. His marriage to Maka's mother didn't last; his habit of flirting around eventually tanked the relationship, and they're now divorced. That said, he's genuinely devoted to both of them despite hanging out at clubs—he's constantly running around yelling about how much he loves his ex-wife (affectionately called "Mama") and Maka, even if Maka herself can't stand him. It bothers him a lot that she resents him, but he keeps trying to be there for her in his own awkward, well-meaning way.
Before he partnered with Mama, Spirit was Dr. Franken Stein's weapon. The two were actually college roommates back in the day, and Spirit still has nightmares about Stein's obsession with dissecting him—memories he'd probably rather forget. His old meister taught him a lot, but those days left some scars, literally and figuratively.
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