Ova - School Days

It includes meta-references to the series' notoriety, including the famous "Nice Boat" meme.

Kokoro Katsura (Kotonoha's younger sister) transforms into a superheroine called "Magical Heart" to fight "forces of evil"—which includes parodied versions of the other main characters. School Days OVA

The School Days anime features two primary episodes that shift away from the dark tone of the main series: 1. Valentine Days and over-the-top comedy.

The girls of the class compete to give chocolates to the protagonist, Makoto, in various romantic (and sometimes absurd) scenarios. School Days OVA

It completely abandons the psychological drama for high-energy action, magic, and over-the-top comedy.