The first two episodes move so fast you barely notice they're setting up a harem, the joke IS the chaos, not the girls. After that it's pure slapstick with a protagonist who actually reacts like a real person instead of a blank slate, which makes every gag land harder. The uncensored dialogue and voice acting sell bits that would die silent on TV, even if the show completely abandons its plot halfway through and never finds it again.
Haruo Yoshikawa thinks he's living a completely normal life until his mischievous sisters blow up his world with a confession: their entire family practices magic. What should be shocking somehow gets weirder when Ayumi shows up, a mysterious girl who insists that Haruo himself has dormant magical potential locked away inside him. She's convinced she can awaken it, and she's not taking no for an answer. What follows is pure chaos wrapped in supernatural hijinks. Haruo gets dragged into a world where spells go hilariously wrong, his sisters meddle constantly, and Ayumi's relentless pursuit of his magical awakening creates an increasingly awkward dynamic. The comedy mines genuine laughs from the clash between his desperate attempts to keep things normal and the impossibility of that goal once magic enters the picture. This is lighthearted fun that doesn't pretend to be anything deeper than it is. If you want a show that prioritizes laughs over logic and doesn't mind getting absurd with its romantic tension, this scratches that itch.