After Inori's heat is well and truly over (which takes more than another whole fucking month, and which involves more usage of his lead pipe than an ideal society would need) he feels like he's sufficiently emotionally stable to try to figure out whether he loves Tōkan. He's not really sure where to start, though, so he asks Harutsugu first.
"And now imagine that you read all of those manga and you reach the conclusion that you don't like him. What are you going to feel then? Are you gonna say 'well I guess that's that, it's been a good run'?"
"—you would be really upset and angry if you lost him, then. And you want to spend more time with him and you want him to be near you even if you're not really talking or doing anything, and you like to touch him and when you wake up in the morning next to him you wanna cry."
"Tōkan is a sucker for narratives, Yamada. A bit too much, and a bit too deep. Calling it 'feelings' matters to him. But you're clearly head over heels for him already and I'm so fucking jealous," and he accidentally crushes his ice cream cone when he says that and has to use a napkin to clean the mess. "...I'm so jealous that you get to have him and I don't. But you're something else, I get that now. So at least... let me live vicariously through you. Love him for me, okay? ...and maybe tell me what it feels like, after."