Makai Tenshi Djibril -Episode 2-

Otonashi Meimi is walking alone in an empty park when the demon Rococo suddenly appears. Rococo users her Eternal Worm attack on Meimi in order to separate the power of Misty Mei from within her body.
Meanwhile, at Naoto's house, Hikari, Naoto's stepsister who was studying abroad, returns home. She starts going to the same school as Naoto, and it worries Rika, Naoto's lover, a little.
"I love you the most in the world." - With these words, Naoto makes love with Rika in the school's nurse's office. However, Misty Mei appears and spirits Rika away. Then, the angel Loveriel appears saying that Naoto has no choice but to have sex with Hikari so that a new Djibril can be born to save Rika.

[From AnimeNFO]