Okasu Bekarazu!! Junketsu Tokku!

In a world where humans undergo animal transformation to survive a deadly virus, a fourteen-year-old boy discovers he may be the last true human. By 2035, beast-human people are the norm, after humanity uses animal genes to escape a virus that leaves other animals unharmed and slowly kills humans. The transformation becomes a stark choice: change or die. Kokuryuu Kazuto is an unusually unathletic student who is nonetheless popular with girls, much to his discomfort. Three girls from the Pure-bred Special Ward tell him that he is actually human—a being who should no longer exist. Kazuto doubts them until he learns that his animal ears and tail are fake, leaving him to face his place in a beast-human world.