From the back cover:
Tsukasa wants Tsukushi and Rui expelled from Eitoku Academy, and he challenges them to a basketball showdown. Later, thanks to Tsukasa’s sister Tsubaki, Tsukushi and Rui are forced to spend a night together. But Rui confesses to Tsukushi that he is still unable to forget about Shizuka.
A basketball showdown?! The girl you love has “sliced [your] heart into ribbons” by smooching your friend, and you challenge them to a basketball showdown?! It turns out that it’s actually Tsubaki’s idea to settle the issue with sports and it’s Rui who suggests basketball, but it’s ridiculous nonetheless. Thankfully the participants realize this, and the game itself isn’t that bad.
Tsubaki has another brilliant idea later—let’s make the new couple who haven’t boffed yet spend the night in a room together! This stupid notion does lead to something good, as Rui admits to Tsukushi that he doesn’t really know how he feels about her and can’t forget Shizuka. Tsukasa, of course, thinks they did the deed.
So, I dunno. Some good things happened in this volume, but Tsubaki and her suggestions just inject a dose of dumb that I don’t particularly care for and make the moments worth getting excited over fewer and farther between.