Ikemen Sengoku: Toki wo Kakeru ga Koi wa Hajimaranai

A typical college student at Kyoto University named "Sasuke Sarutobi" studies time slips as a pastime up until the day he accidentally enters a time slip and is sent to the Sengoku Period. Toyotomi Hideyoshi, Tokugawa Ieyasu, and the renowned "Demon King of the Sixth Heaven," Oda Nobunaga, who accepts Sasuke as a vassal, are among the warriors Sasuke meets upon his arrival. Sasuke discovers his position in an ancient but completely new society by introducing the warlords to a variety of modern ideas, such as playing tennis and sending chain letters.