Pixiv is the place to go for fanarts! Here is the series' tag: https://touch.pixiv.net/tags.php?tag=謙虚、堅実をモットーに生きております! Hmmm...but Aoi-chan mentioned her two brothers (Muscles and Otaku) a few times *and* Reika was curious about them, but they still don't really get to show up... Of course, there still a chance, but so far Imari's brother only serves to give Imari the line about how cute little sisters are better than bratty younger brothers. Oh wait, Imari once joked about how Reika should marry his brother right? Make that three times then. Imari's brother seems to be permanently living overseas though, so even if he does appear, the likelihood of him becoming a permanent fixture is a bit low. Omg. That would be so so cute! I'm a fan of this theory!