The Dangers in My Heartis a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on “thedangersinmyheartmanga.com” fastest updating comic site. The Summary is

Kyoutaro Ichikawa may look like your average middle school student, but in his heart, he dreams of murder. Thus, it is no surprise that the one he wants to kill the most is never far off from his mind: the class idol, Anna Yamada. Reading alone in his beloved school library, he inadvertently begins to rendezvous with Yamada, who comes to secretly gorge on her beloved candies and sweets. Through their interactions, Ichikawa discovers just how much of a ditz Yamada is, and cannot help but support her from the sidelines. Meanwhile, Yamada herself cannot help but tease Ichikawa relentlessly due to his flustered reactions. With an array of heartwarming daily interactions, the distant bond between the two grows into something more than just library acquaintances. Perhaps, in time, Ichikawa will come to realize that his murderous desires have turned into something else entirely.