help me huhu

it's a bl manga and the story revolves around a student who encountered a ghost at the rooftop. the ghost (as far as i remember) committed suicide. he and the student became good friends. they always hang out at the rooftop. the ghost talked about his crush whom he drew a portrait of and believed that his bestfriend does not miss him. when the ghost learned that his crush (his bestfriend btw) always looks at the portrait that he drew, his soul finally rest in peace and perished (that's his unfinished business, i think). the student loved the ghost (this is so saddd). i think it's a oneshot story? pls help me find thissss ╥﹏╥