Ocha Nigosu (お茶にごす。), also known as A Bad Boy Drinks Tea!, is a Japanese manga series written and illustrated by Hiroyuki Nishimori.

It was serialized in Shogakukan's Weekly Shōnen Sunday from April 2007 to July 2009, with its chapters collected in 11 tankōbon volumes.

A 12-episode television drama adaptation premiered in Japan on Amazon Prime Video in March 2021 and was broadcast on TV Tokyo from October to December of the same year.

The story follows the high school delinquent Masaya Funabashi, better known as "Devil Ma-kun", who is trying to reform his image by joining the Japanese tea ceremony club.

[7] In December 2020, it was announced that a 12-episode Japanese television drama adaptation would premiere on TV Tokyo in 2021, starring Nobuyuki Suzuki as Masaya Funabashi.