Bocchi no Otaku de Aru Ore ga, Gakunai Kusshi no Bishoujo-tachi ni Kakomarete Itsunomanika Riajuu Yobawarisareteita

Our main character suffers from a communication disorder due to an event that occurred in his past. He—was a boy name Kaito, and his only friend was a girl that he knew online. He doesn't know the identity of this person at all... maybe it isn't even a girl... However to Kaito, no matter what type of person she was, she was still an important friend. Every day, the people around him would say, "Otaku, gross, you have no presence." Nobody would even come near him except for school reasons. On yet another day of his lonely life, his father remarried—fortunately or unfortunately, it changed his life completely. Kaito obtained a family with a beautiful sister, which would usually be something to be happy about. However, he despaired about it and made an oath in his heart: "This girl, will definitely cry someday!" Gradually, Kaito makes contact with other beautiful girls in the school. Because of them, his peaceful lonely life began to change completely and was thrown into disarray. Will he end up in heaven or hell? (Source: Shousetsuka ni Narou, translated)