It turns out the timid, polite Harumi has a secret admiration for the way Kiriha teases Koutarou, so she does the unthinkable—she asks Kiriha to teach her how to become a bad girl too! In the next story, Clan also asks for something a little unusual. She starts martial arts training under Koutarou and Shizuka, but is she really up to the task when she can barely handle her own feelings? Next, there’s a surprise royal visitor to room 106, and Sanae, Yurika, and Maki decide it’s time for a makeover of magical proportions. Finally, it’s time for the Kisshouharukaze school field trip, complete with surprise confession!

In this collection of side stories: Kiriha and Elfaria go toe-to-toe to decide who gets to take care of Koutarou when he gets sick on vacation, the story of how Yurika’s magical training went when she and Nana first met, and a chance date with Maki and Kiriha in a rather meaningful place. Then, in a very special feature, we get a glimpse into what life would be like between Clan and Koutarou if they started dating.

Summer vacation is right around the corner, but can Koutarou and the invaders manage a ceasefire long enough to actually enjoy it? Luck seems to be on their side when Ruth wins them a trip to a seaside hot spring, but it's not all fun and games with shadowy figures stalking their every move. When push comes to shove, can rivals become allies to save one of their own? Or is it every invader for themselves?

Koutarou at last makes his return to Forthorthe, although it’s not in a very glorious fashion. Stranded on Planet Alaia with Theia and Yurika, he’ll have to figure out a way to use the limited resources they have to get past the imperial troops everywhere if he ever hopes to make it back to safety and the rest of their friends. Fate has a few familiar twists in store, however, as the coup d’état gets off to an ugly start and their enemies show their true colors.

With one of their own in trouble, Koutarou and the others are left reeling. Clan thinks she may have gotten to the bottom of things, but if what she says is true, the crisis they now face has been in the making for thousands of years. But the surprises are far from over there. A strange message for Koutarou could mean a tentative new alliance with a most unexpected partner. The offer comes at a time when they could desperately use the help, but what will the true cost be?

With Forthorthe on the verge of erupting into civil war like it hasn’t seen for thousands of years, Elfaria and the others do what they can to regain the trust of the citizens. But as it turns out, all of Forthorthe has their eyes on her, her daughter... and the mysterious knight in blue armor. Can they win the hearts of the people while trying to keep a very big secret from them? And with the vicious Vandarion plotting against them, it looks their bloodiest battle yet may be looming on the horizon.

Volume 20 is a special collection of side stories. First up, Yurika announces that she’s quitting cosplay—or, at least, that’s the impression the cosclub gets. Next, Sanae and Ruth do a little dream diving. After that, Maki confronts Theia about some unexplained expenses she’s recording in the Satomi knights’ ledger. Then lastly, Shizuka recruits the entire Corona House crew to help out with the cook-off at the cultural festival. The girls will cook while Koutarou judges, and the results are explosive to say the least.

Now that the invaders have come to an understanding of sorts, things are going smoother than ever in room 106. Spring is in the air--tulips, friendships, and potential romances are all about to burst into full bloom. Koutarou and the invading girls have never been happier together, but nothing lasts forever. Things turn dark quickly when they find out that they're going to have to say goodbye to one of their own... and soon. Without even any time to prepare, will the bonds they all share be enough to pull them through?

The evil magical girls are finally making their move to seize the mana pool in room 106, just like Yurika's been saying all along! Koutarou crosses paths with an old enemy, and Maki is forced to decide whether she follows her duty or her heart.

With the end of the year approaching, things are getting busy around Corona House. Even though it's winter vacation, there's a new play to get ready for, Koutarou has picked up a new part-time job that no one seems to know anything about, and Ruth has decided to take up martial arts training. Come January, preparations for "The Silver Princess and the Blue Knight, Part 2" kick into high gear, but when an old rival reappears dead set on revenge, Koutarou may be in for the trip of a lifetime.