As you requested, I will base my answers from the bible:
We see in John 1:14 that Jesus, as God become flesh was "full of grace".
We see in Psalm 103:8 that God is full of mercy and slow to anger.
We see in Romans 5:8 that God demonstrates his love toward us.
Thus, grace, mercy and love are characteristics of God.
* Grace is the withholding of punishment or justice.
* Mercy is being kind, even when it is undeserved.
* Love is a committed delightful affection.
In Hebrews 1:14 we see that angels are "ministering spirits" sent to help us. So, in his grace, mercy and love, God sometimes sends spirits or angels to help us.
So, while love, grace and mercy are not necessarily specific angels or spirits ... according to the bible, angels or spirits can be one way God shows his love, grace and mercy.