Only the Fallen (UnHallowed Series #1) by Tmonique Stephens

Normally, I don't like fictional books about Heaven and Hell. This author takes up an issue of the Fallen Angel. In this series, there are angels that fell that the Father calls the Unhallowed. He has given them a way to redeem themselves. Here we find that Michael offers a way for Gideon to redeem himself. It will forever change him and the angel he fell in love with, but the chance at redemption is worth the cost.