It's practically an americanized remake. You see, Daron met up with Rumiko Takahashi once in an anime convention just when Daron was ironing out the basic concept of Star. Daron's original concept was Star was a chunni as fuck gradeschooler who got bullied and imagined her status as a magical princess with superpowers that fought imaginary monsters. After getting some advice from Rumiko, who basically told Daron to just ape shit from her influences just like she did, Daron decided to ape the basic premise of Star vs. and later presented that to the Disney Execs, a straight up Urusei Yatsura adaptation for the Western world. Of course Daron abhorred Lum attacking the MC with her electric powers and the MC being a massive horndog, and pretty much scoffed at Rumiko at their meeting, intimidating her because Daron was huge and Rumiko was aged tiny Jap, but was enamored with harem, so she pretty much based Star off an extremely idealized version of herself and Marco as an idealized version of her husband who is smart, polite, levelheaded but knows karate, and since she liked harem, she had this idealized version of her husband slowly get a harem, thanks in part because Star met Marco and changed his life. Of course we all know Marco will eventually fuck Star nonstop in the end of the story.
Of course, Daron combined her other influences in there as well, most prominently Sailor Moon, which has pretty much eclipsed whatever flimsy premise Urusei Yatsura had.