Some Canmephians are joined together (conjoined) when they are adults, sharing one part or almost all of a body. This is usually done durring a long lasting marrage, and after a throughal psychological exam of both couples, plus a recoding of both couple's DNA. Such a conjoinment is a very long term committment and is very perament.
Some conjoinments are done magically by Drygers.
Temporary conjoinment of the tails is done as a trial and under looser conditions. Some younger adults have conjoined their tails for long-lasting dates, only to sepearate later when they have no other option.
Polymorphs can conjoin eazily with other polymorphs by their nature, or imitate a conjoined pair.