Higurashi is a homage to Tsukihime.

Good Lord why didn’t it hit me before.

Let’s start with the title. “Higurashi no Naku Koro Ni” in English translates to “When the Cicadas Cry”. This is a reference to a famous scene in Tsukihime, where Shiki gets a glass injection straight to the heart eight years ago. Unfortunately, due to confidentiality issues, I cannot reveal the scene.

Another big homage would be the twin swapping thing. Well, in Tsukihime, we have Kohaku and Hisui, who are twins, and in certain scenes of the game, both sisters switch places. Same thing happens in Higurashi, well, it’s mentioned once. Maybe more in the game. I can’t be too sure. Also, we all love Shion and haet Mion. Mion sucks.
One of the biggest hints of Tsukihime influence is Ciel. Yes, people, Chie-senpai is actually Ciel. Even though it’s not all that apparent in the anime, it’s a whole lot more apparent in the manga and game. She goes fuckin’ nuts when curry is mentioned in the former and judges a curry competition and whips out her trademark weapon in the latter.