Dei Ecchi Ei(2006)

Dei Ecchi Ei

Ai Shiratori is your average junior high school student with a crush on a boy, Hikaru Kamishiro. With a love so rampant and true, and an imagination as wild as any girl's Ai sometimes has rather... ecchi dreams. But none of those dreams could ever prepare her for the reality that came to her in the form of the Archangel Raphael.

You see, Hikaru Kamishiro is not your average boy. Hell has plans for him and Heaven isn't about to let those plans come to fruit. While Hell sends their Hell's Apostles to get Hikaru to commit the seven deadly sins and drag him into hell, Heaven sends their secret weapon: Ai. What is Ai's mission? Nothing short of consummating her love with her beloved Hikaru... but wait by consummating you mean... sex?! Can Ai handle the Archangel's request and save her true love?

(Source: Manga-Heaven)