The World God Only Knows

Dating sim master Keima Katsuragi wants nothing more than to immerse himself in the 2D world, chasing digital girlfriends. But when the so-called "Capturing God" answers a mysterious email from an unknown sender, Keima finds himself chasing down real-life ladies in an attempt to help the peppy demon Elsie de Lute Irma capture "lost souls" escaped from the depths of hell. Now, lest the explosive collar around his neck detonate, Keima must convince various girls to fall in love with him in order to scare out the souls hiding in their hearts.

Synopsis from Anime News Network