Don't Toy with Me, Nagatoro-san is a Manga/Manhwa/Manhua in english language, SUGGESTIVE series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.nl fastest updating comic site. The Summary is

Our nameless—and spineless—hero (only known as "Senpai") is a second-year high school student and loner who spends his afternoons at the Arts Club room. He attracts the attention of one of his schoolmates, a sadistic freshman girl named Nagatoro. However, in between the bullying and teasing, something else begins to blossom. A lovey-dovey(…?) story between a shy nerd and an S-Dere (Sadistic Tsundere) begins.