Ore no Imoto ga Konna ni Kawaii Wake ga Nai 15 (Dengeki Bunko) [Light Novel]

[Machine Translation] ( Under the fireworks, I confess to Black Cat ) It is June of my senior year of high school. The head of the game research club suggested that we go on a research camp during the summer vacation. At first, Kurokono did not intend to participate, but with the support of his father and sister, he decided to join the camp. Once the camp started, I, together with Kuroko, enjoyed chatting with Akagi and his siblings on the bullet train, watching the sunset on the deck of the ferry, taking an open-air bath, having a test of one's courage, and enjoying fireworks. We spend the best summer vacation on a remote island full of nature. During these days, we meet a girl who calls herself Yu Makijima. Yuu, who is well versed in fortune-telling and the occult, gets along well with Kuroko, and asks her to accompany him on an expedition to investigate the "Tennyo lore" passed down on the island. There we have a strange experience.

「花火の下、俺は黒猫に告白する」高校3年の6月。ゲーム研究会の部長から夏休みの取材合宿を提案された俺たち。最初は参加するつもりのなかった黒猫だが、父や妹からの後押しを受け参加を決める。合宿が始まると、俺は黒猫と一緒に、新幹線の中で赤城兄妹と歓談したり、フェリーの甲板で夕陽を眺めたり、露天風呂に入ったり、肝試しをしたり、花火をしたり。自然たっぷりの離島で、最高の夏休みを過ごす。そんな日々の中、俺たちは槇島悠と名乗る少女と出会う。占いやオカルトに精通する悠は、黒猫と意気投合し、島に伝わる“天女伝承”の取材に同行を申し出る。そこで俺たちは、不思議な体験をする。