My Girlfriend Wants Me to Share My Harem?

I am Steve.And there is something strange about the setting of the world I have reincarnated. Wait! is that my girlfriend ?! And what the hell is she doing! I have to do something about this.My heart and brain in unison: "STOP HER!!!!"My lower body: "Can I join in?"The maid on the book cover: "Don't look at me, I have no idea how things turned out like this"Me: "Is all of this happening because I reincarnated without being hit by a truck?"

If you want to know how I got in this mess, you got to tag along with me in this comic story.