Mr. Nobunaga's Young Bride.

Nobunaga was a teacher who was waiting for that kind of dating sim event to happen in real life. One day, a 14 year old girl named Kicho appears in front of him, saying that she's his wife?! Apparently she came from the Warring States era and seems to have mistaken Nobunaga for the Oda Nobunaga and tells him that she wants to have his children. An age-gap love comedy featuring a teacher with a dating sims brain and a princess with a warring states era brain!!