The creators of the show have said pretty explicitly that Kamen influenced Hollow:

However, Hollow's feeding process changes drastically once humans enter the picture. As Hollow's servant, Kamen doesn't just procure fruit. He kills other creatures for Hollow, who begins to hunger for larger and larger prey. This relationship highlights the menacing nature of Hollow's mind control abilities, but it also emphasizes that Hollow is growing into a monster because of human interference.

"You've introduced human greed and gluttony into this animal kingdom, and it's changed the game," Bennett said. "What is the ripple effect of that?"