Angelic Guardian

You conjure a minor celestial manifestation to protect a creature you can see within range. A faintly glowing image resembling a head and shoulders hovers within 5 feet of the target for the duration. The manifestation moves to interpose itself between the target and any incoming attacks, granting a +2 bonus to AC. 

Also, the first time the target gets a failure on a Dexterity saving thrown while the spell is active, it can use its reaction to reroll the save. The spell then ends.