So, I Can't Play H, Vol. 3

At Ryosuke's place, Lisara and now Qru have taken up residence. With steamy situations arising day in and day out, Ryosuke is constantly sapped of vigor, but for a lecherous loser like him, it's a sad and happy life at the same time. And as if he had any more spirit energy to spare, Ryosuke is joined by the pinup model Iria, who's just transferred into his class! But is it true that she's actually a grim reaper?!
An astounding battle of differences breaks out!
Were test scores always determined by "bust size"?!