Responses
I think Asahi just want's to tease Masato. And as for saying why he is Naru's best friend, it's because Naru likes teasing other people as well. So in conclusion both Naru and Asahi really like to tease/annoy other people. And well, Masato can be quite easily teased in this case, because he's not so open about his relationship in front of other people. Especially with those that he's close to. At least that's what I think. ╮( ̄▽ ̄)╭

Can somebody explain what happened here? Don't really understand Asahis reaction:
http://www.mangago.zone/read-manga/love_nest_minaduki_yuu/uu/mpn_chapter-1990404/pg-32/