Call of the Lonely
In the depths of your solitude, and when your hope withered on the branch, you were granted a companion you can call on. You never have to be alone again. This companion is Friendly toward you but is deeply unsettling to your allies.
Never Alone.
When no other creature can see you, you can use a Bonus Action to call your companion, which appears in an unoccupied space within 10 feet of you. It takes the form of a person or a vague silhouette, and it uses the Doppelganger stat block. It is Friendly toward you and acts as your ally, and it takes its turn on your Initiative in combat. It disappears after 1 hour, when it dies, when you die, or when you use an action to politely dismiss it. When it disappears, it drops anything it was wearing or carrying.
Once you use this Bonus Action, you can't use it again until you finish a Long Rest.
Precocious Friend.
The companion sometimes appears with trinkets, Cursed Curios, or other items. It might tell you where it got them, or it might not (GM’s choice). If it took the object from someone who misses it or wants it back, that could create difficulties for you.
Unsettling Presence.
While your companion is summoned, both it and you exude a frightful air that unnerves your allies. While the companion is summoned, a creature that isn’t Hostile toward you that starts its turn able to see you or the companion must succeed on a DC 15 Wisdom saving throw or have the Frightened condition until the start of its next turn.