Harpy summon ring

[Royalucario]

In act 1 you see the harpys and I always found them to be strong and unique to that area. I was thinking of a ring you find there or buy at the first trader after saving the kid that would alow you to summon a harpy as a ritual or just let you infinitely summon as many as you want. It would not be balanced but I really would love to do a solo run through the game as leader of a pack of harpys. If anyone has any ideas or work arounds please let me know. Or if there's ways to spawn summons to your party.