Takeru Nagayoshi(永吉たけるNagayoshi Takeru, born on October 21, 1978 in Fukuoka Prefecture, Japan) is a Japanese manga artist. He is notable as the author of the Sumire 16 sai!! series. He debuted on Weekly Shonen Magazine in 2006 with the manga series Sumire 17 sai!!, then later moved to Magazine Special continuing the series but renaming to Sumire 16 sai!!.