I like Haruki's story, but I'm really invested in Kanata's. Haruki is all-in on Aniki, while Kanata is suffering doubts about what he really wants, which is more interesting. I wish the conversations with Haruki's mom had been more in-depth about Kanata's emotions/desires, and a little less lewd bait (just a little).
Also: I love how everyone mentally wallpapers over Okaa-san's words on succubi over in their minds. She really has a powerful don't-notice aura about her, and she probably can't turn it off completely.