Senpai with someone else? I don't want that! For 10 years at least!
Dang, Akari is adorable here with her cheeks getting smooshed like that. Not those cheeks, mind you. Her oniichan is also the ultimate wingman. I don't remember ever seeing a big brother become a wingman for his little sister in any manga or anime. I like him now. Someone give that man a girlfriend.
Good luck Akari, indeed. Even if "Yua" wasn't a love rival, she'll still need all the luck she can get with a dense love interest like him.