Someone who simps for the once-ler. Mainly tumblr user or 13/14 year old girls who have seen the Lorax to many times. Once-ler simp makes you breedable and submissive, you may also be a simp for Daniel from camp camp. These type of people probably read wattpadd fics self inserts like one direction.
A fictional capitalist created by Dr. Seuss in 1971 as the main antagonist. He is also included in the 1972 The Lorax 25 minute short-film and the 2012 The Lorax made by Illumination. The Onceler produced a product called Thneeds, using the tuffs (leaves) of truffula trees. Near the end of the story, he runs out of trees and is forced to close his business. He gives a small child the last truffula seed to birth a new forest. The Onceler portrayed in the 2012 film spawned a fandom of simps, which in turn caused the creation of tumblr sexyman. In this fandom, he was shipped with himself, and fan created oncelers. However, this fandom died after a few years.