Father Callahan's account in Wolves of the Calla, has them as able to pass for human at a distance. However, the Pere's suspicions were soon aroused; these beings, while wearing human clothes and using human transport, do not get either quite right. Their fashion sense is garish, favoring yellow raincoats, checkered suits and overly flashy jewellery; their cars are equally likely to draw attention, being both classic American made and yet appear to be brand new. Closer views reveal artificial-looking faces and oozing red patches upon their foreheads. The truth, as finally revealed in the sixth volume when Susannah Dean rips the mask away, is that the Can-toi have rat-like heads. The apparent wound on their foreheads is actually an orifice through which the mask - itself a living organism, grown for that particular purpose - can breathe.
Ted Brautigan, a man possessing psychic abilities, ties up most of the loose ends in his own account in the final book. The Can-Toi are a hybrid race descended from matings between human beings and Taheen, a more classical animal-headed humanoid. Their attempts to pass as human are not merely for the sake of espionage, but a genuine quasi-religious belief that they actually are becoming human. As with their dress sense and their cars, however, they miss the mark again; their names are famous names drawn from 'hume' culture, frequently mismatched, while their humour is crude and rudimentary, with great amusement found in turning pictures upside down. Such behavior explains their nickname, the 'Low Men'. Even Finli O'Tego, a full-blood Taheen with the head of a weasel, considers the Can-Toi very odd.
It would appear that some of the Can-Toi identify as taheen rather than human. The roller-skating doctor at Algul Siento has taken the Taheen name of Gangli Tristrum and eschews a mask, while the nurse who attends Susannah and Mia also goes bare-headed.
- The short story "Low Men in Yellow Coats" in the collection Hearts in Atlantis involves Ted Brautigan running from Can-Toi attempting to recapture him.
- In From a Buick 8 the titular Buick is alive, and transports objects to an alternate world. It is possible that it is a car of a low man.
- In Desperation, Collie Entragien makes mention of them in relation to Tak.