ah first love. i was like that when i was younger too, wanting a formal confession lol. but learning context in relationship helps a lot. they didn't have to do that formal "i love you" thing, it's different for every couples. and as i see it, both main characters understood what passed between them and that's the most important thing.
Oh! And that time when they were confronting that "nut-job" stalker fan, Yoru was like "I love him one-sidedly" and OH MY FRICCKIN GOSH when they got home, Yoru hugged Asaichi and said he's cool, and then Asaichi goes: "it's not like it's one-sided" well we all know Asaichi totally likes Yoru too, but that part was so cute for me. (づ ̄ ³ ̄)づ

it’s been a while but asaichi has had great character development, from what i remember.
asaichi used to have yoru do things for him for his own pleasure. and now he seems to really like yoru.
i just can’t remember if he confessed to yoru or not. hopefully there will be some fluff in the future.