Harem anime with a small, chubby protag

I tried searching this one by memory to no luck, so I've come to ask here

As per the title, the protagonist was kid-sized and chubby. He lived in a big mansion-like place with some pretty girls, with personalities typical of a harem.

I specifically remember one of the harem girls to be this kind of girl. She was a samurai/ninja type of character.

In the only scene I remember, that girl was arguing with the protagonist on a rooftop. She slipped, but the protagonist saved her, said some cheesy line, and she immediately blushed and seemingly fell in love.

Honestly, it was so cliché it was terrible, but it's been like 10 years and I want to watch it again.

Hopefully someone can give me a hand.