The return of romance, drama, and pure-hearted romance. Junjou Romantica 2 (the sequel). Back to the beloved couples, and their perils in their forbidden relationships. Misaki Takahashi, from the main couple, thought that one Usami was a handful, until he meets another. Their relationship starts to fall down hill once again, but as always they find a way to make steamy love in the end. As for the other couples, ups and downs, lefts and rights occur, but all ends in sweet lovely bliss. Misaki and the Usami crisis, Hiroki with his pride, Shinobu with his age difference with his lover, Nowaki's patience and love, Miyagi's past-love and his present love, and Usagi-san and his family, these couples really got a lot of love and problems in their pure-hearted, forbidden romance.
With the return of love, drama, and pure-hearted romance, we return to the troubled couples, focusing on the parallels between each of their relationships. Misaki Takahashi thought that Haruhiko Usami was a handful, until a new love interest appears. This causes their relationship to once again head downhill, each hoping to find a way to reconcile in the end. For the other couples, episodes focus on Hiroki's problems with his pride, Shinobu's age difference from his lover, Nowaki's patience and love, Miyagi's past and present love, plus Usagi-san and his family issues. This all adds up to each of the couples having a lot of problems to overcome in their pure-hearted, forbidden love lives.
Summary taken from: MyAnimeList