School Days:

Get someone pregnant, get killed, pregnant chick gets killed, crazy chick is seen on a yacht holding your head. Or something.

No really though.

In the anime version, Sekai believes she is pregnant with Makoto’s child, but is asked to get an abortion by Makoto. Under the emotional stress induced by Makoto’s request, she stabs him with a kitchen knife. Soon after, Kotonoha discovers Makoto’s dead body and calls Sekai to the roof of the school using Makoto’s cellphone. After a brief exchange, where Kotonoha shows Sekai the school bag with Makoto’s severed head inside, Kotonoha attacks and kills Sekai with a saw then cuts her womb open in search of the fetus. She then concludes that Sekai was a liar and that Sekai was not pregnant. Whether this statement is reliable is questionable as she was psychologically unstable at that point in time. The ending scene shows Kotonoha on her family yacht clinging to Makoto’s severed head.