The kiss between Bella Hadid and Miquela Sousa, part of a Calvin Klein commercial last month, struck many viewers as unrealistic, even offensive.

Ms. Hadid, a supermodel, identifies as heterosexual, and the ad sparked complaints that Calvin Klein was deceiving customers with a sham lesbian encounter. The fashion company apologized for “queerbaiting” after the 30-second spot appeared online.

But Ms. Hadid, at least, is human. Everything about Ms. Sousa, better known as Lil Miquela, is manufactured: the straight-cut bangs, the Brazilian-Spanish heritage, the bevy of beautiful friends.

Lil Miquela, who has 1.6 million Instagram followers, is a computer-generated character. Introduced in 2016 by a Los Angeles company backed by Silicon Valley money, she belongs to a growing cadre of social media marketers known as virtual influencers.