5E Warlock Subclass: The Beloved

From publisher blurb: In the span of one’s existence, those you know eventually move beyond the Veil. Sometimes when a creature moves on, if there are things left unresolved, they return as spirits or corrupted undead—and sometimes, through the unconditional bond they shared with another, they can reach through the void and gift protection upon their dearest loved one. From their rest beyond the Veil, they vow to watch over those they loved in life and keep them safe from harm.