Shibou End wo Kaihi shita Galge no Heroine ga Ore no "Nikkichou" wo Yonde Himitsu wo Shitta Rashii

I reincarnated as Satoshi Iriya, a mob character in a gal game world. But for some reason, the heroines are worshiping me?! And what's more, they're all complete yanderes.. "I'm sorry. Please don't throw me away. Don't hate me." "..I only have eyes for you. We'll be together forever, right?" The actual protagonist is right there, so why are they all coming after me?! By the way.. where did my diary go? (Source: Kadokawa, translated)