Hive

The Hive are parasitoid beings belonging to a hive mind. They cannot exist on their own, and thus bind to other sentient beings via a consensual process known as the Oath. Pairing to an individual melds their consciousnesses and connects them mto all members of the Hive.
If an individual does not accept the Hive willingly, there can potentially be disastrous results, from causing irreversible mental damage to death. Forcing the Oath on a being is strictly against the Hive's system of beliefs, even in life or death situations.