Forest's Les Naufragés du Temps (hereafter referred to as 'LNdT') series tells the story of a couple of humans who were placed into cryonic hiberation in the 1990s as humanity faced being wiped out through pestilence. Christopher and Valérie awake in 2981, a time when Earth is threatened by alien, intelligent rats.
Of the many characters that Chris and Valerie encounter is Tapir, the largest criminal in the cosmos - another universe, allegedly. Tapir is depicted as a sword-wielding giant in a flowing cloak, who, despite originating from another universe, looks very much like a Brazilian tapir.
The third volume of LNdT was released in English as Lost in Time: Labyrinth in 1986, although Tapir was renamed The Boar (presumably because the intended target market was not as familiar with tapirs as it ought to have been). It has been described as a landmark of modern science fiction.
Forest died on 30 December 1998, having suffered from severe asthma for many years.