Ai no Jikken
Synopsis
"I like you, Yuichi." "Huh?!" "I wanted to tell you before I took time off school. Is that weird? I'm sorry." Yuichi was suddenly confessed to by his childhood friend, Chihiro. And Chihiro will be taking time off school... What's going on?! However, Yuichi begins to notice Chihiro's increasing number of injuries and unsettled emotions, as well as the strong attraction he feels towards Chihiro, whose true feelings only hurt himself. Young, inexperienced and clumsy. But that's what makes them all the more sinful and heartwarming! A story of a life changing romance between two childhood friends. (Source: Libre, translated)
Background
Ai no Jikken began as a web comic released on the author's pixiv page. The series was released in book format with extra chapters by Libre on May 9, 2015.